Answer:
3 m/s²
Explanation:
Sum of forces in the x direction:
∑F = ma
68 N − 23 N = (15 kg) a
a = 3 m/s²
What is density?
O A. The net energy transferred between two objects
B. A measure of mass per unit volume
O C. A measure of the movement of molecules
O D. The force exerted on an area
Answer:
B. A measure of mass per unit volume
Explanation:
Mass and volume are intimately correlated with density. In reality, it explains the precise nature of the connection between the two. We can determine an object's density by dividing its mass by volume. Thus, option B is correct.
What best defines about density?The mass or amount per unit of volume of a substance determines its density. Density is calculated using the formula mass/volume. It is considered to have a low density if a mass has a high volume but a tiny mass.
The volume and subsequently the density of a material typically alter when it changes its phase or state of matter. Temperature is the primary component, even though pressure can also affect how a material changes state.
Water availability, climate, relief (the contour of the terrain), vegetation, soils, and the accessibility of renewable energy sources are physical elements that impact population density. Social, political, and economic variables altering humans all have an impact on population density.
Therefore, A measure of mass per unit volume.
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Is a motor a load that can be found in a circuit?
Answer:
yes you can find a motor in a circuit
The governor of state A earns $53,745 more than the governor of state B. If the total of their salaries is $289,405, find the salaries of each.
Answer:
Sa is the salary of the governor of state A
Sb is the salary of the governor of state A
"The governor of state A earns $53,745 more than the governor of state B. "
This means that:
Sa = Sb + $53,745
"If the total of their salaries is $289,405,"
means that:
Sa + Sb = $289,405
Then we have two equations:
Sa = Sb + $53,745
Sa + Sb = $289,405
Now, we can replace the first equation into the second equation:
(Sb + $53,745) + Sb = $289,405
2*Sb = $289,405 - $53,745 = $235,660
Sb = ($235,660)/2 = $117,830
and:
Sa = Sb + $53,745 = $117,830 + $53,745 = $171,575
Governor of state A earns: $171,575
Governor of state B earns: $117,830
A ball is launched from the ground with a horizontal speed of 30 m/s and a vertical speed of 30 m/s. When will the ball hit the ground again? A. 4 s B. 6 s C. 3 s D. 5 s
Answer:
B. 6 s
Explanation:
Given in the y direction:
Δy = 0 m
v₀ = 30 m/s
a = -10 m/s²
Find: t
Δy = v₀ t + ½ at²
0 m = (30 m/s) t + ½ (-10 m/s²) t²
0 = 30t − 5t²
0 = 5t (6 − t)
t = 6
A ball is launched from the ground with a horizontal speed of 30 m/s and a vertical speed of 30 m/s, the ball will hit the ground again at approximately t = 6 seconds. The correct option is B.
We can examine the ball's vertical motion to predict when it will strike the ground once more.
h = v0t + (1/2)g[tex]t^2[/tex]
0 = 30t + (1/2)(9.8) [tex]t^2[/tex]
Simplifying the equation:
4.9 [tex]t^2[/tex] + 30t = 0
Factorizing the equation:
t(4.9t + 30) = 0
Solving for t in 4.9t + 30 = 0:
4.9t = -30
t = -30 / 4.9
t ≈ -6.1
Since time cannot be negative in this context, we discard the negative solution.
Therefore, the ball will hit the ground again at approximately t = 6 seconds.
Thus, the correct answer is B. 6 s.
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show the relationship between the quantity of matter and the mass of objects
Answer:
actually quantity of matter present in a body is its mass.
Which statement describes one feature of a closed circuit? Charges do not flow. Bulbs will not shine. The circuit is broken. The circuit is complete.
I inferred you've referring to a close electrical circuit.
Answer:
The circuit is complete.
Explanation:
A closed electrical circuit is indeed a complete circuit. Also, it allows charges to flow, the bulbs in the circuit will shine and it is not broken.
It is termed closed circuit because there is no brokage in the series of electrical wires or the switch; which may prevent the free flow of current or charges. Thus, a feature that marks closed circuits is that they are complete.
Answer:
The circuit is complete.
Explanation:
Resistor R1 and R2 are connected in parallel to an emf source that has negligible internal resistance. What happens to the current through R1 when the third resistor R3 is connected parallel with R1?
The current does not change.
All three resistors are connected directly to the power source, and are unaware of each other.
Select the type of energy involved in each step. You turn on the burner of a gas stove. The gas ignites. The gas warms the water in the pan.
Answer:
You turn on the burner of a gas or stove - mechanical energy.
The gas ignites - Chemical energy.
The gas warms the water in the pan - Thermal energy.
Letícia leaves the grocery store and walks 150.0 m to the parking lot. Then, she turns 90° to the right and walks an additional 70.0 m to her car. What is the magnitude of the displacement of her car from the grocery store exit?
Answer:
165.529454
Explanation:
According to the Pythagorean Theorem for calculating the lengths of a right angle triangle's sides, a^2 + b+2 = c^2, where c is the longest side (and the side opposing the right angle). So in your case it would be 150*150 + 70*70 = 27400. And √ 27400 is your answer.
Two runners start at a distance of 10 miles from each other. They run towards each other at a constant velocity of 5 mph. A fly takes off from runner one’s nose at time zero. The fly has a constant velocity of 20 mph and flies between the runners. Find the total distance that the fly has traveled when the runners collide.
Answer:
The fly will travel 20 miles before the runners collide with each other.
Explanation:
Since the runners are both traveling at the same speed, they will meet and collide in the exact middle of each other which is 5 miles away from their starting point. Since they are traveling at 5 mph, it will take exactly one hour before they collide. The fly is going 20 mph so it will travel 20 miles before the runners collide in one hour.
As light from a star spreads out and weakens, do gaps form between the photons?
Answer:
There are no gaps in space between the photons as they travel. If you look at light as a wave, then there no gaps unless specifically placed there on purpose. ... The light from a distance star indeed spreads out and weakens as it travels, but this just reduces the wave strength and does not introduce gaps.
a truck is moving with a certain uniform velocity. it is accelerated uniformly by 0.75 m/s^2.after 20 seconds, the velocity becomes 72 km/h. find the initial velocity
Answer:
[tex]\boxed{V_{i} = 5\ m/s}[/tex]
Explanation:
Given:
Acceleration = a = 0.75 m/s²
Time = t = ?
Final Velocity = [tex]V_{f}[/tex] = 72 km/hr = 20 m/s
Required:
Initial Velocity = [tex]V_{i}[/tex] = ?
Formula:
a = [tex]\frac{V_{f}-V_{i}}{t}[/tex]
Solution:
For [tex]V_{i}[/tex] the formula becomes:
[tex]V_{i} = V_{f}-at[/tex]
[tex]V_{i}[/tex] = 20 - (0.75)(20)
[tex]V_{i}[/tex] = 20 - 15
[tex]V_{i}[/tex] = 5 m/s
In Case: If you want it in km/hr:
[tex]V_{i}[/tex] = 5 * 3.6
[tex]V_{i}[/tex] = 18 km/hr
Answer:
5 m/s
Explanation:
acceleration = 0.75 m/s²
time = 20 s
final velocity = 72 km/h = 20 m/s
initial velocity = ?
Apply formula for initial velocity.
[tex]u=-at+v[/tex]
[tex]\sf a=acceleration\\t=time\\v=final \: velocity\\u=initial \: velocity[/tex]
Solve for u.
[tex]u=-(0.75)(20)+ 20[/tex]
[tex]u=-15+20[/tex]
[tex]u= 5[/tex]
A ray of light is projected into a glass tube that is surrounded by air. The glass has an index of refraction of 1.50 and air has an index of refraction of 1.00. At what minimum angle will light in the glass tube be totally reflected at the glass/air interface?
Answer:
θ = 41.8º
Explanation:
This is an internal total reflection exercise, the equation that describes this process is
sin θ = n₂ / n₁
where n₂ is the index of the incident medium and n₁ the other medium must be met n₁> n₂
θ = sin⁻¹ n₂ / n₁
let's calculate
θ = sin⁻¹ (1.00 / 1.50)
θ = 41.8º
Mustang Sally just finished restoring her 1965 Ford Mustang car. To save money, she did not get a new battery. When she tries to start the car, she discovers that the battery is dead (an insufficient or zero voltage difference across the battery terminals) and so she will need a jump start. Here is how she accomplishes the jump start:
Explanation:
To jump start she needs
1. Jumper cables
2. Power source/jump box/ portable batteries.
The positive end of the jump cable will be connected to terminal of the car battery and the jump box, likewise the negative terminal to complete the circuit for a successful jump start to be accomplished
why does a hot air balloon fall when the air inside is not heated
A series circuit is shown in the diagram below. What is the potential drop across R₁? (R₂ = 20 Ω, R₂ = 40 Ω, R₃ = 60 Ω, V = 60 V) (Ohm's law: IR)
Answer:
Option B. 10 V.
Explanation:
The following data were obtained from the question:
Resistor 1 (R₁) = 20 Ω
Resistor 2 (R₂) = 40 Ω
Resistor 3 (R₃) = 60 Ω
Potential difference (V) = 60 V
Next, we shall determine the total resistance of the circuit.
The circuit is in series connection. Therefore the total resistance (R) can be obtained by adding up R₁, R₂ and R₃ together as shown below:
R = R₁ + R₂ + R₃
R = 20 + 40 + 60
R = 120 Ω
Therefore, the total resistance in the circuit is 120 Ω
Next, we shall determine the current flowing in the circuit.
Note: The same current will flow through each resistor since they are in series connection.
The current flowing in the circuit can be obtained as follow:
Potential difference (V) = 60 V
Total resistance (R) = 120 Ω
Current (I) =..?
V = IR
60 = I x 120
Divide both side by 120
I = 60/120
I = 0.5 A
Therefore, the current flowing in the circuit is 0.5 A
Now, we can calculate the potential drop across R₁ as follow:
Resistor 1 (R₁) = 20 Ω
Current (I) = 0.5 A
Potential difference cross R₁ (V₁) =.?
V₁ = IR₁
V₁ = 0.5 x 20
V₁ = 10 V
Therefore, the potential difference across R₁ is 10 V.
Imagine that your standing on a beach but cannot swim. Your friend encourages you to walk into the surf zone created by incoming deep-water waves that have a wavelength of 30 meters. Would it be safe to walk out to where the waves are breaking? Explain how you arrived at your answer.
Answer:
It would not be safe to walk out to where waves are breaking due to the effect of rip currents
Explanation:
The water depth in the surf zone is between 5 to 10 meters deep and with a wavelength of 30 meters, the speed of the wave is considerably fast such that control for safety may be difficult
Also the speed of the wave is directly related to the depth of the water which means that where the wave described above is fast as well as the rip current, also the water depth is expected to be considerable for a non swimmer
It is best to seek for sign post regarding safe areas and do not go into the water where there are no lifeguards or marked safe zones.
It won't be safe to walk out to where the waves are breaking.
This is because the wavelength is 30 meters which is a characteristic of
areas with significant water depth in the range of 5-11 meters.Under these
conditions the waves are usually very fast and may get swept with the
current from the water waves when trying to run from it.
It is recommended that we stay in areas where the depth is noted as not
being much and should always seek help and clarity from the life guards so
as to prevent drowning and death.
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A physics professor uses an air-track cart of mass m to compress a spring of constant k by an amount x from its equilibrium length. The air-track has negligible friction. When she lets go, the spring launches the cart. What cart velocity should she expect after it is launched by the spring
Answer:
v = √k/m x
Explanation:
We can solve this exercise using the energy conservation relationships
starting point. Fully compressed spring
Em₀ = [tex]K_{e}[/tex] = ½ k x²
final point. Cart after leaving the spring
[tex]Em_{f}[/tex] = K = ½ m v²
Em₀ = Em_{f}
½ k x² = ½ m v²
v = √k/m x
If you precisely measure the position of a particle, you __________. If you precisely measure the position of a particle, you __________. destroy information about its momentum convert it into a wave cause it to interfere cause the particle to be annihilated
Answer:
Destroy information about the speed of the particle
Explanation:
This is according to Heisenberg's Uncertainty Principle states that there is inherent uncertainty in the act of measuring a variable of a particle. Commonly applied to the position and momentum of a particle, the principle states that the more precisely the position is known the more uncertain the momentum is and vice versa.
Which of the following statements are true? (mark all that apply)
A) Adaptive optics corrects for atmospheric distortion by following the distortion of a bright star, possibly an artificial star created by a laser, and rapidly changing the shape of a mirror using computer-controlled actuators to compensate for the distortion.
B) Improvements in technology will eventually allow the entire electromagnetic spectrum to be observed from high mountaintop observatories.
C) X rays from astronomical objects can only be detected from telescopes in space or in high altitude rockets.
D) The best observing sites for optical telescopes are atop remote mountains.
E) Radio telescopes must be carried to high altitudes by balloons in order to detect this type of radiation.
Answer:
The answer(s) for this question are as followed: A, C, & D
Explanation:
I hope this helped, let me know if i missed any.
Please help me with this question ASAP.
In a a potentiometer circuit, a 1m long potentiometer wire PQ of resistance 10 ohms is connected in series with a cells of e.m.f. 9V with internal resistance 3 ohms Calculate:
i The p.d. across PQ
ii. The e.m.f. of a cell which has a balance point of 75cm.
Answer:
i. 6.923 V
ii. The e.m.f. = 22.5 V
Explanation:
i. The given parameters are;
Length of potentiometer = 1 m
The resistance of the potentiometer = 10 Ω
The e. m. f. of the attached cell = 9 V
The current, I flowing in the circuit = e. m. f/(Total resistance)
The current, I flowing in the circuit = 9 V/(10 + 3) = 9/13 A
The potential difference, p.d. across the 1 m potentiometer wire = I × Resistance of the potentiometer wire
The p.d. across the potentiometer wire = 9/13×10 = 90/13 = 6.923 V
ii) Given that the 1 m potentiometer wire has a resistance of 10 Ω, 75 cm which is 0.75 m will have an e.m.f. given by the following relation;
[tex]\dfrac{E}{R_{balance}} = \dfrac{V}{R_{cell}}[/tex]
Where:
E = e.m.f. of the balance point cell
[tex]R_{balance}[/tex] = Resistance of 75 cm of potentiometer wire = 0.75×10 = 7.5 Ω
[tex]R_{cell}[/tex] = Resistance of the cell in the circuit = 3 Ω
V = e.m.f. attached cell = 9 V
[tex]\dfrac{E}{7.5} = \dfrac{9}{3}[/tex]
E = 7.5*3 = 22.5 V
The e.m.f. = 22.5 V
If you could travel from one planet to another
in our solar system, which of the following
would change the most?
A. your weight
B. your mass
C. your height
D. your width
A boat floats in a lake. When the boat moves the force of resistance is proportional to the velocity of the boat. Initially the boat is at rest. A person walks from the stern to the bow of the boat. What will be the position of the boat long time after the person stopped moving?
Answer: Contant.
Explanation:
You are given that When the boat moves the force of resistance is proportional to the velocity of the boat. This means that the total momentum on the boat is equal to zero. Then the boat remains at a certain position.
When a person walks from the stern to the bow of the boat, the boat will tend to move in the opposite direction with equal magnitude of momentum. The magnitude of forces will thereby cancel out.
The person will be seen moving while the boat moves in the opposite direction.
If no external force is acting on the boat, the sum of the momentum of the person and the boat will be equal to zero. And the boat will remain at rest.
The position of the boat long time after the person stopped moving will therefore remain the same.
Fill in the appropriate word or term for the following statements.
a. -150 mV
b. Voltage-gated
c. resting
d. super- depolarization
e. +30 mV
f. +15 mV action
g. action
h. close
i. open
j. hyperpolarization
1. Voltage-gated K -50 mV channels remain open, causing a ___________of the membrane. The membrane is now in its relative refractory period.
2. The membrane is at the____________ potentials occasionally generating graded potential. open
3. Voltage-gated K channels____________and the resting potential of the membrane is restored.
4. At about ____________voltage-gated Na* channels are inactivated, and voltage-gated K channels open. Kt exits the cell and repolarizes the membrane. At this time, the membrane is in its absolute refractory period.
close
5. An action potential is triggered when the threshold potential of about____________ is reached. Voltage-gated Na+ channels open. Na* diffuses into the cell and depolarizes the membrane.
Answer:
1 j
2 C
3 H
4E
5A
Explanation:
3. An electron with a mass of 9.11 X 10^-31 kg is moving at a speed of 2.19 X 10 m/s. What is the kinetic energy of the electron?
Answer:
[tex] 2.18\times 10^{-30} \:J[/tex]
Explanation:
[tex] K.E._{Electron}= \frac{1}{2} mv^2 \\\\
= \frac{1}{2} \times 9.11\times 10^{-31}\times (2.19\times 10)^2 \\\\
=4.555\times 10^{-31}\times 4.7961\times 10^2 \\\\
=4.555\times 10^{-31+2}\times 4.7961 \\\\
=21.8462355\times 10^{-29}\\
=2.18462355\times 10^{-30}\\
=2.18\times 10^{-30} \:J\\[/tex]
WILL MARK U AS BRAINLIEST...... An aeroplane is taking off with a velocity of 360 km/h at an angle of 30° with the horizontal. find its horizontal and vertical componnent velocities.
Answer:
x=180√3. or 311.7 and y= 180km/h
Explanation:
y= sin30° × 360km/h
y= 0.5 × 360km/h
y= 180km/h
x=cos30° × 360 km/h
x=√3/2*360km/h
x=180√3. or 311.7
A skateboarder rides down the street. When his feet push down on the
skateboard, what is the reaction force?
Answer:
the skateboard pushes up
Explanation:
newton's 3rd law says for every action, there's an equal and opposite reaction, so when his feet push on the skateboard, the skateboard pushes back up.
Answer:
the skateboard pushes up
Explanation:
PHYSICS
A small sphere of mass 2g is released from rest in a large vessel filled with oil, where it
experiences a resistive force proportional to its speed. The sphere reaches a terminal speed of 5.00
cm/s. Determine the time constant given the following masses.
Answer:
5.10×10⁻³ s
Explanation:
At terminal velocity, the acceleration is 0.
Sum of forces in the y direction:
∑F = ma
bv − mg = 0
mg = bv
m = bv / g
m/b = v/g
τ = v/g
τ = (5.00 cm/s) / (980 cm/s²)
τ = 5.10×10⁻³ s
You are observing the radiation from a distant active galaxy and you notice that the amplitude of the signal varies in strength regularly over a certain period. The maximum possible size for the source of this radiation can now be calculated from the:____________
Answer:
Period of the signal.
Explanation:
So, this question is all about a concept in physics or astronomy which is called or known as Radiation Astronomy and Galactic Nuclei that are active. This concept talks most about Quasars; a powerful radiating object which derives its power from black holes.
When You take a look at Quasars, we get the to know that the more you think you can see, the more they move away from us.
Thus, when "You are observing the radiation from a distant active galaxy and you notice that the amplitude of the signal varies in strength regularly over a certain period. The maximum possible size for the source of this radiation can now be calculated from the "PERIOD OF THE SIGNAL.
NB: not the amplitude but the period.
Assignment: Ultrasound and Infrasound Research Exploration Ultrasound and infrasound are categories of sound with different frequencies. These categories of sound can be used for a variety of different applications. In this research assignment, you will take a look at the industrial applications of ultrasound and infrasound. Your essay should do the following things: • Define and describe in detail (and in your own words) ultrasound and infrasound • Describe how ultrasound and infrasound are used in specific industrial applications and provide detailed examples. When conducting your research, remember to gather information from multiple sources. Start your research by defining ultrasound and infrasound. Then find ideas about industrial applications. The essay should be about 350-450 words, which is 1-1.5 typed pages, double-spaced, using 12-pt. font. Check the rubric to review how you will be graded for this assignment. plz no funny answers
Answer:
Infrasound vs. Ultrasound: Infrasound is sound that is below the lower limit of human hearing, below 20 Hz, and ultrasound is above the upper limit of human hearing, above 20,000 Hz. Individuals use infrasound - this recurrence run for checking seismic tremors and volcanoes, graphing rock and oil developments underneath the earth. Infrasound is described by a capacity to get around hindrances with little scattering.
For instance, a few creatures, for example, whales, elephants and giraffes convey utilizing infrasound over significant distances. Torrential slides, volcanoes, seismic tremors, sea waves, water falls and meteors produce infrasonic waves. Symptomatic ultrasound, additionally called sonography or demonstrative clinical sonography, is an imaging technique that utilizes high-recurrence sound waves to create pictures of structures inside your body. The pictures can give important data to diagnosing and treating an assortment of ailments and conditions.
Explanation:
idk how many words this is but its a start for u to add on to and i hope this helps and its in my own words - pls mark me brainiest
Answer:
Ultrasound vs. Infrasound Research Exploration
Beyond the limit of human hearing, ultrasound is above 20,000 Hz. Under the limit of human hearing, infrasound is below 20 Hz. Individuals use infrasound - this recurrence run for checking seismic tremors and volcanoes as well as graphing rock and oil developments beneath the earth. Infrasound is described by a capacity to get around hindrances with little scattering.
For instance, creatures like whales, elephants and giraffes convey utilizing infrasound over significant distances. Torrential slides, volcanoes, seismic tremors, sea waves, waterfalls and meteors produce infrasonic waves. Symptomatic ultrasound, additionally called sonography or demonstrative clinical sonography, is an imaging technique that utilizes high-recurrence sound waves to create pictures of structures inside your body. The pictures can give important data to diagnosing and treating an assortment of ailments and conditions.
(Not turned in yet, but this is what i have so far. Good luck 8th graders <33)
-Sav xx