a boy whose mass is 40kg runs up a flight of 30 step each 150 mm in 60 second find the averse power develop expansion explain the anomalous of two of water​

Answers

Answer 1

The average power developed by the boy during the climb is approximately 29.4 W.

What is power?

In physics, the amount of energy transferred or converted per unit time is called power.

total height = number of steps x height of each step

total height = 30 x 0.15 m = 4.5 m

Given, time = 60 s

As power = work done / time

work done = force x distance

force = mass x gravity

mass is boy's mass (40 kg) and gravity is acceleration due to gravity (9.81 m/s²).

force = 40 kg x 9.81 m/s² = 392.4 N

The distance that the boy moves is equal to the total height that he has climbed: distance = total height = 4.5 m

work done = force x distance

work done = 392.4 N x 4.5 m = 1765.8 J

power = work done / time

power = 1765.8 J / 60 s

power ≈ 29.4 W

Therefore, the average power developed by the boy during the climb is approximately 29.4 W.

As for the anomalous behavior of water, water has a higher boiling point and melting point as compared to other substances with similar molecular weight. This is due to the strong hydrogen bonding between water molecules, which requires more energy to break the bonds and change the state of water from solid to liquid to gas.

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Related Questions

help as soon u can pls! due in 45 mins!!

Which statement correctly represents a mineral?

1. any naturally forming substance made from one element

2. any chemical substance which forms naturally in the Earth

3. an element which is made into an object

4. any substance which develops in the ground

Answers

Minerals are any chemical substance which forms naturally in the Earth

Define mineral.

Minerals are those substances found in foods and in the earth that our systems require for healthy growth and development. Calcium, phosphate, potassium, sodium, chloride, magnesium, iron, zinc, iodine, chromium, copper, fluoride, molybdenum, manganese, and selenium are among the nutrients that are crucial for good health.

Compounds found only in living creatures are typically not considered minerals according to geological definitions. However, some minerals, like calcite, are frequently biogenic or, in terms of chemistry, are organic molecules (such as mellite). Additionally, living things frequently produce inorganic crystals (like hydroxylapatite), which are also found in rocks.

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The cooling system of a laser system fails. As a result, 64 kcal of heat are absorbed each minute by the laser rod in the laser system. The laser rod has a mass of 5 kg. It has a specific heat of 0. 3 kcal/kg • Co.


Find: How much the temperature of the rod increases each minute, in 0C

Answers

The temperature of the laser rod increases by 21.33 degrees Celsius each minute due to the failure of the cooling system.

When heat is transferred to an object, its temperature increases. The amount of temperature increase depends on the amount of heat transferred, the mass of the object, and its specific heat.

To calculate the temperature increase of the laser rod, we can use the formula:

ΔT = Q / (m * c)

where ΔT is the change in temperature, Q is the heat absorbed, m is the mass of the laser rod, and c is the specific heat of the material.

In our case, the laser rod is a closed system, and the heat added is 64 kcal per minute.

Substituting the given values, we get:

ΔT = 64 kcal / (5 kg * 0.3 kcal/kg•Co)

ΔT = 21.33 Co

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HELP ASAP
Discuss how the government uses tax credits, direct payments, and deficiency payments to
subsidize renewable energy.

Answers

For eligible renewable energy technology and projects, a number of tax credits, grants, and loan programmes are offered by the federal government.

Why does the government promote the use of renewable energy sources?

Fossil fuels are burned to produce energy, which produces a sizable amount of greenhouse gas emissions that contribute to global warming. Even when taking into account the entire life cycle of the technologies, the majority of renewable energy sources produce negligible to no emissions.

Why are subsidies for renewable energy good?

Subsidies have helped reduce dependency on fossil fuels by expanding the use of renewable energy sources. This is crucial for lowering greenhouse gas emissions and preventing an increase in global temperatures.

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In your opinion, Is the big bang theory a valid explanation for the beginning of time?
If so, what areas of research do you think has the greatest possibly for more discovery?
If not, what problems in the theory leads you to reject it? What might be an alternate theory?

(please give me a good long well thought out answer)

Answers

Answer:

I believe that the Big Bang Theory is a valid explanation for the beginning of time. Areas of research that have the greatest potential for more discovery include dark matter and dark energy, the nature of the inflationary period, and the origin of the matter-antimatter asymmetry.

Problems with the Big Bang Theory that lead me to reject it include the lack of a satisfactory explanation for the origin of the initial conditions of the universe, the lack of a satisfactory explanation for the origin of the matter-antimatter asymmetry, and the lack of a satisfactory explanation for the origin of the inflationary period. An alternate theory could be the Cyclic Universe Theory, which proposes that the universe goes through an infinite cycle of expansion and contraction.

If the device is kept reverse biased, we know that the voltage across the device will remain roughly constant at the zener voltage. If d5 is carrying a minimum current of 5ma (down) and d6 is carrying a current of 5ma (down), what is the minimum current through r1?

Answers

The minimum current through R1 will be 10mA.

Using Ohm's Law (V = IR), we can find the minimum current through R1 as follows:

Vr1 = Vz5 + Vz6

where Vr1 is the voltage across resistor R1.

Therefore, the minimum current through R1 is:

Ir1 = Vr1 / R1

Assuming that R1 is a standard value resistor (e.g., 1kΩ), and the Zener voltages are each 5V, the voltage across R1 will be:

Vr1 = Vz5 + Vz6 = 5V + 5V = 10V

Therefore, the minimum current through R1 will be:

Ir1 = Vr1 / R1 = 10V / 1kΩ = 10mA

Current is the flow of electric charge through a conductor or material. It is defined as the rate of flow of electric charge, measured in units of amperes (A). One ampere is equivalent to the flow of one coulomb of electric charge per second.

Electric current is caused by the movement of charged particles, typically electrons, in a circuit. When a voltage is applied to a conductor, it creates an electric field that causes electrons to move through the conductor. This flow of electrons constitutes an electric current.

The direction of electric current is defined as the direction of flow of positive charges, even though the actual charges that move are electrons, which are negatively charged. Electric current can be direct current (DC), where the flow of charge is in one direction, or alternating current (AC), where the direction of flow periodically changes.

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The gravitational potential energy of a person on a 4 m high diving board is 1800 J. What is the person's mass?

Answers

Answer:

45.9 kg

Explanation:

GPE = mgh

m = GPE / gh = (1800 J) / (9.8 m/s²)(4 m) = 45.9 kg

Can someone help me with these? Thanks!


Solve the following vector problems

8. A ship's maximum speed is 22km/hr to the South, What is its speed if there is also a current of 3km/hr to the South?


9. A ship's maximum speed is 22km/hr to the South, What is its speed if there is also a current of 3km/hr to the North?


10. What is your displacement if you travel 50m to the right, and then return 20 meters to the left?


11. What is your displacement if you drive 2 km North, then 4 km East, then 2 km South, and finally 4 km West?

Answers

The ship's speed relative to the ground is 25 km/hr to the South.

The displacement is zero, which means that the final position is the same as the initial position. The movements to the North and South cancel out, and the movements to the East and West cancel out.

What is velocity?

Velocity is a vector quantity that describes the rate at which an object's position changes over time.In other words, velocity is an object's speed in a specific direction. The velocity of an object is typically represented by a vector, which has both magnitude (the speed of the object) and direction.

The ship's speed relative to the water is 22 km/hr to the South. If there is a current of 3 km/hr to the South, the ship's speed relative to the ground is the vector sum of its speed relative to the water and the velocity of the current. Since the two velocities are in the same direction, we can simply add them to get:

velocity relative to the ground = 22 km/hr to the South + 3 km/hr to the South = 25 km/hr to the South.

Therefore, the ship's speed relative to the ground is 25 km/hr to the South.

Similar to the previous problem, the ship's speed relative to the ground is the vector sum of its speed relative to the water and the velocity of the current. However, this time the current is going in the opposite direction, so we need to subtract the velocity of the current from the ship's speed relative to the water:

velocity relative to the ground = 22 km/hr to the South - 3 km/hr to the North = 22 km/hr to the South + 3 km/hr to the South = 25 km/hr to the South.

Therefore, the ship's speed relative to the ground is 25 km/hr to the South.

The displacement is characterized by the difference between the final and initial positions. In this case, the initial position and the final position are the same, so the displacement is zero. We can represent the two movements using vectors:

50 m to the right = +50 m i

20 m to the left = -20 m i

The displacement vector is the vector sum of these two vectors:

displacement = +50 m i - 20 m i = +30 m i

Since the x-component of the displacement vector is positive, the displacement is to the right.

We can represent the four movements using vectors:

2 km North = +2 km j

4 km East = +4 km i

2 km South = -2 km j

4 km West = -4 km i

The displacement vector is the vector sum of these four vectors:

displacement = +2 km j + 4 km i - 2 km j - 4 km i = 0 km i + 0 km j

Therefore, the displacement is zero, which means that the final position is the same as the initial position. The movements to the North and South cancel out, and the movements to the East and West cancel out.

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Dispersion of light by a prism is due to the change in ______

a) frequency of light
b) speed of light
c) scattering
d) none of these

Answers

Answer:

(b) the speed of light depends on the index of refraction of the medium thru which it is traveling - different colors have different indices of refraction and are refracted at different angles

An excited physic student is in a cart rolling down a hill at 12 m/s If the cart and student have a combined kinetic energy of 4896 J, what is the mass of the student and cart combined?

Answers

Answer:

17.0 kg

Explanation:

The kinetic energy (KE) of the system can be expressed as:

KE = (1/2)mv^2

where m is the mass of the cart and student combined, and v is the velocity of the cart.

We know that KE = 4896 J and v = 12 m/s. We can rearrange the equation to solve for m:

m = 2KE/v^2

m = 2(4896 J) / (12 m/s)^2

m = 17.0 kg

Therefore, the mass of the student and cart combined is 17.0 kg.

A packing crate of weight 50N is placed on a plane inclined at 35° from the horizontal . If the coefficient of static friction between the crate and the the plane is 0.65 , will the crate slide down the plane?​

Answers

Answer:

A packing crate of weight 50N is placed on a plane inclined at 35°from the horizontal. If the coefficient of static friction between the crate and the plane is 0.65, will the crate slide down the plane? asked by Siyam February 26, 2022 1 answer normal force = m g cos 35 = 50 cos 35 = 41 Newtons so max friction force up slope = 0.65 * 41 = 26.6 N

Explanation:

The center grinds up plastic for recycling, but the workers forgot to label the type of plastic. The workers found that the plastic has a mass of 2.25 g and a volume of 2.5 cm. What is the density of the plastic? What type of plastic was it? JUSTIFY your answer.

Answers

Density of the plastic is 0.9 g/cm³.

The type of plastic collected are yogurt cups and plasticwares.

What is density of a substance?

Density of a substance is defined as the mass per unit volume of the substance.

Here,

Mass of the plastic, m = 2.2 g

Volume of the plastic, V = 2.5 cm³

So, density, ρ = m/V

   ρ = 2.25/2.5

   ρ = 0.9 g/cm³

Recyclable plastics are sorted on the basis of their densities. Here, the density of the collected plastic is 0.9 g/cm³. So, the plastic material must be  yogurt cups and plasticwares.

Hence,

Density of the plastic is 0.9 g/cm³.

The type of plastic collected are yogurt cups and plasticwares.

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A force is applied to a 1 kg mass and produces
4.1 m/s
2
acceleration.
What acceleration would be produced by
the same force applied to a 13.4 kg mass?
Answer in units of m/s
2
.

Answers

The 2.4 m/s² acceleration would be produced by the same force applied to a 13.4 kg mass.

What is acceleration ?

The pace at which speed changes is known as acceleration. Acceleration typically, but not always, indicates a change in speed. Because the direction of an object's velocity is shifting even while it follows a circular course, it continues to accelerate.

What is force?

A body can change its state of rest or motion when an external force acts on it. It is directed and has a magnitude.

As we know that force= mass × acceleration

So F₁=m₁×4

F₂=m₂×6

now for combined system total acceleration will be "a"= F/ m₁+m₂

m₁= F/4

m₂= F/6

so put the value of m₁ and m₂

​Therefore, 2.4 m/s² acceleration would be produced by the same force applied to a 13.4 kg mass.

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Two equal masses placed 2m apart have a gravitational attraction of 6. 7*10-9 N compute the value of the mass ( assume,g=6. 7*10-11

Answers

For the given question value of mass=20kg. The formula for gravitational attraction between two masses is:

F = G * (m1 * m2) / r^2

where F is the gravitational force, G is the gravitational constant, m1 and m2 are the masses, and r is the distance between the centers of the masses.

Given:

F = 6.7 * 10^-9 N

r = 2 m

G = 6.7 * 10^-11 N m^2 / kg^2 (gravitational constant)

Since the two masses are equal, we can write m1 = m2 = m.

Substituting the given values into the formula and solving for m, we get:

6.7 * 10^-9 N = 6.7 * 10^-11 N m^2 / kg^2 * (m^2 / (2 m)^2) * m^2

Simplifying:

6.7 * 10^-9 N = 6.7 * 10^-11 N * m^2 / 4

Multiplying both sides by 4:

m^2 = (6.7 * 10^-9 N * 4) / 6.7 * 10^-11 N

Simplifying:

m^2 = 4 * 10^2 kg

Taking the square root of both sides:

m = 20 kg

thus, each mass has a value of 20 kg.

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A ball of mass 20 g moving at 10 m s¹ horizontally collides with another ball of mass 40 g that is at rest. After collision the 20 g ball has a velocity of 4 m s at an angle of 50° relative to its original direction. Calculate the total change in kinetic energy of the system. A. 1.21 x 10-21 B. -121 x 10-21 C. 112 x 10-2 D. 815 x 102 E. -518 x 10-1​

Answers

Answer:

We can use conservation of momentum and conservation of energy to solve this problem.

Conservation of momentum:

Initial momentum = final momentum

m1v1 + m2v2 = (m1 + m2)v'

where m1 = 20 g = 0.02 kg, v1 = 10 m/s, m2 = 40 g = 0.04 kg, v2 = 0, v' is the final velocity of both balls after collision.

Solving for v':

v' = (m1v1 + m2v2)/(m1 + m2)

v' = (0.02 x 10 + 0.04 x 0)/(0.02 + 0.04)

v' = 6.67 m/s

Conservation of energy:

Initial kinetic energy = final kinetic energy

(1/2)m1v1^2 + (1/2)m2v2^2 = (1/2)(m1 + m2)v'^2

where v' is the final velocity calculated from conservation of momentum.

Solving for the total change in kinetic energy:

ΔKE = (1/2)(m1v1^2 + m2v2^2) - (1/2)(m1 + m2)v'^2

ΔKE = (1/2)(0.02 x 10^2 + 0.04 x 0^2) - (1/2)(0.02 + 0.04) x 6.67^2

ΔKE = -0.518 J

Therefore, the answer is (E) -518 x 10^-1.

A University of Rochester student decided to depart from Earth after his graduation to find work on Mars. Before building a shuttle, he conducted careful calculations. A model for the velocity of the shuttle, from liftoff at t=0 s until the solid rocket boosters were jettisoned at t = 46 s, is given
by
v(t) = 0.001832667³0.082592 +34.52t - 5.65

Using the model, estimate (in feet per second)
The absolute maximum value ____
The absolute minimum value ____

Answers

Using the model, the absolute maximum value of acceleration is 21.698 m/s² and the absolute minimum value of acceleration is 14.597 m/s² between liftoff and the jettisoning of the solid rocket boosters.

What are solid rocket boosters?

Solid rocket boosters (SRBs) are large rocket engines used to provide the majority of the thrust required for a spacecraft during its initial launch phase. They are called “solid” because they contain solid propellant, that burns at a controlled rate to produce thrust.

In the given problem:

We know,

v(t)=0.001500000t³-0.08t²+16.02t-2.37

Acceleration will be derivative of velocity

Hence, a=dv/dt=0.0045t2-0.16t+16.02

at t=0,a=16.02 m/s²

Now the maximum acceleration will be at endpoint i.e., t=57.5s

so at t=57.5 s, a=21.698 m/s²

For minimum acceleration, a'(t)= 0.009t-0.16<0

t<17.77

Minimum acceleration will be at t=17.77 s, a(t)=14.597 m/s²

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The question is incomplete, but most probably the complete question is,

A University of Rochester student decided to depart from Earth after his graduation to find work on Mars. Before building a shuttle, he conducted careful calculations. A model for the velocity of the shuttle, from liftoff at t = 0 s until the solid rocket boosters were jettisoned at t = 57.5 s, is given by (in feet per second). Using this model, estimate:

the absolute maximum value = ??

and absolute minimum value - ??

of the ACCELERATION of the shuttle between liftoff and the jettisoning of the boosters.

The figure shows two wave pulses that are
approaching each other.
Which of the following best shows the shape
of the resultant pulse when the centers of the
pulses, points P and Q, coincide?

Answers

Option 3 shows the shape of the resultant pulse when the centers of the

pulses, points P and Q, coincide.

What is a pulse of a wave?

A pulse of a wave is a single disturbance or vibration that travels through a medium, carrying energy without permanently displacing the medium. It is a type of wave that is characterized by a single disturbance or oscillation that travels through a medium, such as air or water, and creates a temporary disturbance in the medium's equilibrium. A wave pulse can be described by its amplitude (the height of the disturbance), its wavelength (the distance between successive peaks or troughs), and its speed (the rate at which the disturbance travels through the medium).

Q's crest amplitude = Q's Trough amplitude= P's Crest amplitude

and P's wavelength = Q's wavelength

then when you lay them on top of each other

Q's crest combines in phase with the first half of P's crest and they double where as

Q's trough combines out of phase with the second half of P's crest and they negate each other

resulting in something that looks like choice 3

Therefore, Option 3 is the correct answer.

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Select all the correct location on the image .
Which items matter

Answers

Just the phone and battery should be where they should be on the photographs.

What is the definition of a matter?

The term "matter" refers to a substance that is composed of several kinds of particles, occupies space, and has inertia. The numerous kinds of particles each have a unique mass and size, according to the fundamentals of current physics. The electron, proton, and neutron are three of the most well-known instances of material particles.

Which best encapsulates matter?

All objects with mass and volume are considered to be matter (takes up space). It is usually pretty easy to show that the everyday items we interact with have mass and occupy space.

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An Atwood's machine consists of two masses, m and M2, which are connected by a massless inelastic cord that passes over a pulley, Fig. 8-47. If the pulley has radius R and moment of inertia I about its axle, determine the acceleration of the masses mi and m2, and compare to the situation in which the moment of inertia of the pulley is ignored. [Hint: The tensions Fri and Fm are not
Fr
equal. We discussed this situation in Example 4-13, assuming
I = 0 for the

Answers

The expression for the acceleration is the same in both cases, indicating that the moment of inertia of the pulley does not affect the acceleration of the masses.

An Atwood's machine consists of two masses connected by a rope that passes over a pulley. The acceleration of the masses can be found by applying Newton's second law to each mass separately. The force due to gravity and the tension in the rope are the only forces acting on the masses.

If we consider the moment of inertia of the pulley, the acceleration can be found using the net forces on each mass. However, if we ignore the moment of inertia of the pulley, the acceleration can be found using the net force on the system. However, the expression for the acceleration is the same in both cases, meaning that the moment of inertia of the pulley does not affect the acceleration of the masses.

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please help thank you

Answers

Explanation:

itd D because a and b both have something to represent the answer

Identify the direction of net force. A car is driving across a flat roas ,assume no air resistance

Answers

Assuming the car is driving across a flat road with no air resistance, the direction of net force acting on the car will depend on the direction of the car's motion and the forces acting on it.

If the car is traveling at a constant velocity, then the net force acting on it is zero. This is because the forces acting on the car - such as the force of the engine, friction from the tires, and air resistance - are balanced and cancel each other out. However, if the car is accelerating or decelerating, then there is a net force acting on it. For example, if the car is accelerating forward, then the net force acting on it is in the forward direction. This is because the force of the engine pushing the car forward is greater than the opposing forces, such as air resistance and friction. Similarly, if the car is decelerating, then the net force acting on it is in the opposite direction of its motion. This is because the opposing forces are greater than the force of the engine, causing the car to slow down.

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Samples of differnt materials a and b have the same mass but the sample of a is higher in density which statement could explain why this is so

Answers

The constituent particles of material A are heavier than those of material B.

Why density differ -

A material with smaller, more heavy, and closely spaced atoms will have a higher density. A substance's density will decrease if its bigger, lighter atoms are separated from one another more widely.

The densities of solids, liquids, and gases are determined by the separations between the particles in each state of matter.

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As force increases acceleration _______________________________________________. As force decreases acceleration ________________________________________________.

Answers

The words that fill the blanks are;

increases

decreases

What is the relationship between force and acceleration?

Force and acceleration are directly proportional to each other, according to Newton's second law of motion. The law states that the acceleration of an object is directly proportional to the force applied to it, and inversely proportional to its mass. Mathematically, this can be expressed as:

F = ma

where F is the force applied to an object, m is its mass, and a is its resulting acceleration.

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What is the SI unit for mass? Give the full name, not the symbol.
Give your answer.

Answers

Answer: The kilogram, symbol kg, is the SI unit of mass.

Explanation: It is defined by taking the fixed numerical value of the Planck constant h to be 6.626 070 15 × 10-34 when expressed in the unit J s, which is equal to kg m2 s-1, where the meter and the second are defined in terms of c and ΔνCs.

Answer: The answer is kilogram (kg)

Explanation:

The two elements will bond or not bond into one ratio

Answers

Ionic compounds can be created when elements from Groups 1 and 17 mix one to one ratio.

To create ionic compounds, group 1 and group 17 elements can combine one to one.

In addition, group 8A (or VIIIA) of the periodic table contains the noble gases or inert gases helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon. As a result, if any elements from this group are present, they will not bond (Rn).

The name of these elements refers to how little they react with other elements or compounds. An example of bonding is, when carbon and oxygen atoms join in a 1:2 ratio, carbon dioxide is produced; when they combine in a 1:1 ratio, carbon monoxide, or CO, is produced.

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DESPERATE HELP. 80 POINTS. PLEASE PHYSICS

Answers

Henry can use a simple machine, such as a ramp or lever, to help him lift the apple baskets into the truck. By using a ramp, Henry can reduce the force needed to lift the basket by increasing the distance over which he applies the force. Alternatively, he could use a lever to amplify his force and lift the basket with less effort. By positioning the fulcrum of the lever in the right spot, Henry can apply a smaller force to lift the basket. This way, Henry can use his limited strength and still get the job done efficiently.

A recycling center has a 0.125 m° box filled with one type of plastic. The full box has a mass of 120 kilograms. What is the density of the plastic? What type of plastic is in the box? JUSTIFY your answer.

Answers

The density of the plastic found inside the box would be = 960kg/m³

How to calculate the density of the box?

The volume of the box at the recycling center= 0.125m³

The mass of the full box = 120kg

The formula use to calculate the density of the plastic = mass/volume.

That is ; Density = mass /volume = kg/m³

Density = 120/0.125

= 960kg/m³

The type of plastic that is in the box is LDPE (low density polyethylene). This is because the density calculate fell within the range of 940–960 kg/m3.

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Complete question:

A recycling center has a 0.125 m³ box filled with one type of plastic. The full box has a mass of 120 kilograms. What is the density of the plastic? What type of plastic is in the box? JUSTIFY your answer.

A person who weighs 50 N climbs 100 stairs up. Each stair is 0.2 m high. The work done is

Answers

Answer:

Explanation:

Given that ,

A man who weights is 50N climbs up 100 steps of a stair

each step is 0.2m high

mg=50N

Height at 100 steps , h=100×0.2=50 m

Change in potential energy , =mgh=50×50=2500 J

So, Work done by the man , W=2500 J

a 2.6 kg rock is dropped from a height of 10 m with what speed will it strike the ground ignore air resistance

Answers

Answer:

V = sqrt(2gh)

V = sqrt(2 * 9.8 * 10)

V = sqrt (196)

V = 14 m/s

Answer:

V = sqrt(2gh)

V= sqrt(29.8 10)

V = sqrt (196)

V=14 m/s

What is the wavelength of a sound wave that has a speed of 680 m/s and a frequency of 220 Hz? (With full explanation)

Answers

Answer:

3.0909 m

Explanation:

Given,

Wave speed = 680 m/sfrequency = 220 Hz

We need to find the wavelength of sound wave :

We know that ,

[tex]{ \underline{ \boxed{ \sf{F = \dfrac{v}{\lambda}}}}}[/tex]

where,

F is frequency, v is wave speed,[tex]\sf\lambda[/tex] is wavelength

on substituting the values we get :

[tex]\dashrightarrow \sf \: 220 = \dfrac{680}{\lambda} \\ \\ \dashrightarrow \sf \: \lambda = \frac{680}{220} \\ \\ \dashrightarrow \sf \:\lambda = 3.0909 \: m\\ [/tex]

Hence,

Wavelength of sound is 3.0909 m

Lubricants reduce friction by replacing sliding friction with fluid friction.

True or False

Answers

Answer:

true

Explanation:

By adding a thin layer of oil or even water between two objects, you convert the sliding friction to fluid friction.

Other Questions
Which trait in the table has the least phenotypic plasticity to changes in the environment?7. (05.05 MC) The graph below shows the phenotypic plasticity of three different traits in four distinct environments: (3 points) Phenotypic Plasticity of Different Traits 7 6 Trait Value LLLL IL 1 0 Environment A Environment D Environment Environment C Environment Types Trait A Trait 8 Trait Which trait in the table has the least phenotypic plasticity to changes in the environment? a. Traits B and C b. Traits A and C c. Trait B d. Trait A PLEASE HELP ASAP Question 4(Multiple Choice Worth 2 points)(Line of Fit MC)Data was collected on the amount of time that a random sample of 8 students spent studying for a test and the grades they earned on the test. A scatter plot and line of fit were created for the data.scatter plot titled students' data, with points plotted at 1 comma 80, 2 comma 70, 2 comma 80, 2 comma 90, 3 comma 80, 3 comma 100, 4 comma 90, and 4 comma 98, and a line of fit drawn passing through the points 0 comma 70 and 1 comma 75Find the y-intercept of the line of fit and explain its meaning in the context of the data. 80; a student who studies for 0 hours is predicted to earn 80% on the test 70; a student who studies for 0 hours is predicted to earn 70% on the test 10; for each additional hour a student studies, their grade is predicted to increase by 10% on the test 5; for each additional hour a student studies, their grade is predicted to increase by 5% on the test at noon a weatherman recorded the temperature of each city in the area. What was the highest temperature? Mr. McGregor has a carrot garden, but a certain rabbit always seems to sneak in and ruin his harvest. Mr. McGregor asked a gardening friend about how he could alter the carrot population to prevent this sneaky critter from stealing his goods! His friend informed him that carrots longer than 12 inches are too long for the rabbit to pull them out from the ground. He also ran some calculations and found that the additive genetic variance of his carrots' length is 0.54 and the total phenotypic variance is 0.68. If the current carrots average 10.2 inches and Mr. McGregor wants to produce a generation with an average length of 12 inches, what should be the average length of the carrot plants he selects to breed? Which phrase is the best definition of the word cosmopolitan What are examples of common diagnostic services workplaces? Select all that apply Triangle JKL is an equilateral triangle with two of its vertices at points J and K. What are the coordinates of point L? why is it so hard for managers to internalize the sunk-cost concept when making decisions? I recently took a review test and it talked about amount of error (percent error) . The question said that , the estimate number of balls in each bag was 86. It turned out to be 104. What is the percent of error? Round to the nearest tenth. I wrote 17.3%. The teacher said it was wrong and claimed that you had to divide it by expected, not real. (Formula is (expected-real)/real.)) Can someone help me out, am I wrong or the teacher? Discuss two ways in which you could deal t effectively with anxiety during an examination session list the possible rational roots of P(x) given by the rational roots theorem for P(x)=3x^3-4x^3-x^2-7 How did agriculture allow for the development of civilizations? A rat is trying to get food from a garbage can, but is chased away by a crow. The crow eats the food, and the rat must find other food. Based on thisinformation, what is the relationship between the crow and the rat? (1 point)O The relationship is mutualistic.O The relationship is competitive.O The relationship is predator-prey.O The relationship is parasitic What is the value of x? Please help me i need this to pass :(( please help me i need your help. find the value of x In this figure, the unshaded region represents a painting and the shaded region represents a frame around the painting. All angles are right angles.(a) What is the area of the painting? square inches(b) What is the area of the frame and painting? square inches(c) What is the area of the frame? square inchesHELP ME AS FAST AS POSSIBLE, WILL GIVE BRAINLIEST Listen to the audio and then answer the following question. Feel free to listen to the audio as many times asnecessary before answering the question.What is Jorge's problem? 0:00/0:12O He wants to watch television.O His mother can't drive him to school.O He can't find his shoes.He doesn't want to make his bed.d returnSave and ExitNextSubmit Work is the quantity of _____. used to move an object. how do i answer that?!