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Answer:

The work you did in climbing the stairs is the force you applied (your weight) times the distance you moved upward (the height of the stairs.) So yes, climbing stairs is work done.

Explanation:

Hope this helped, nya~ :3

Answer:it equals 0

Explanation:hope this is a good answer

Angular velocity is the ratio of angular displacement to time. Then the number of turns by the shaft is zero.

The rate of change of angular displacement is called angular velocity. It is a vector quantity.

We know that the angular velocity formula

[tex]\rm Angular \ velocity = \dfrac{Angular \ displacement}{time}[/tex]

The motor shaft turns through between the time when the current is reversed and the instant when the angular velocity is zero.

Then the number of turns will be

[tex]\rm Number \ of\ turns = Angular \ velocty \times time \\\\Number \ of\ turns = 0 *time \\\\Number \ of\ turns = 0[/tex]

The number of turns by the shaft is zero.

More about the Angular velocity link is given below.

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Answer:

walked: 17 meters

displacement: 1

Explanation:

so you add 9+8 and the displacement is 1 b/c when you moved back those 8 meters you were still 1 meter away from where you where originally standing

The neutron has no charge, and a mass of slightly over 1 amu. Some scientists propose the neutron is made up of a proton and electron-like particle. The electron is a very small particle located outside the nucleus.

Electron: -1

Neutron: 0

Proton: +1

Answer:

m V1 = (m + M) V2 conservation of momentum

T = time to fall 2 m

2 = 9.8 / 2 T^2    initial vertical velocity zero

T^2 = 4/9.8       T = .639 sec

Sx = V2 * .639 sec     distance traveled horizontally

V2 = 4 /.639 = 6.26 m/sec

V1 = (m + M) / m * 6.26 m/sec       from first equation

V1 = (600 + 10) / 10 * 6.26 m/s = 382 m/s

There seems to be some confusion on units

Note that 382 m/s is a reasonable answer for speed of bullet

1100 ft/sec is reasonable for a .22 cal bullet

1100 ft/sec / 3.28 ft/m = 335 m/sec

Answer:

Explanation:

The wavelength of the wave given it's velocity and frequency can be found by using the formula

[tex] \lambda = \frac{c}{f} \\[/tex]

where

c is the speed of the wave

f is the frequency

From the question we have

[tex] \lambda = \frac{0.5}{50} = 0.01 \\ [/tex]

We have the final answer as

Hope this helps you

Hi there!

We can begin by converting 130 km/h to m/s:

[tex]\frac{130km}{1hr} * \frac{1hr}{3600s} * \frac{1000m}{1km} = 36.11 m/s[/tex]

Find the acceleration associated with this velocity change in the given time frame:

vf = vi + at (vi = 0 m/s)

vf = at

vf/t = a

36.11/80 = 0.45 m/s²

Now, we can calculate Net Force using Newton's Second Law:

∑F = ma

∑F = (1200)(0.45) ≈ 540 N

Answer:

come into conflict or opposition.

"in his work, politics and metaphysics collide

Answer: A force can change the direction in which an object is moving

Explanation: A bigger force of an object will produce a bigger change in motion

Answer:

p=I×B

Explanation:

If a current 'I' flows through a given element in your circuit, losing voltage 'V' in the process, then the power 'P' dissipated by that circuit element is the product of that current and voltage.

The sum of numbers is the total of two or more numbers added together.

Numbers is the arrangement of digits used to count, measure, and label. There are different types of numbers such as whole numbers, integers, natural numbers and many more.

The four basic mathematical operations are addition, subtraction, multiplication and division.

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Answer:Work is a measurement of energy.

Power is a measurement of energy per time.

So, power measures how fast work is done.

If we raise 1kg up to a height of 1 meter it takes a certain amount of work. It doesn't matter if it takes us 1 second or 1 hour to raise it. It takes more power, energy per second, to raise it in 1 second than to raise it in one hour.

An engines power rating is in horsepower. A higher horsepower car engine will get a certain car up a hill more quickly than if it had a lower horsepower engine. Even though both engines did the same amount of work in getting the car up the hill

Answer:

work is a measurement of energy, but power is how much energy it takes. Two people could do the same amount of work. Sally and James. James may finish his work in 2 days due to the amount of power he puts in, but it may take Sally a week.

Answer:

[tex]\boxed {\boxed {\sf 98 \ J}}[/tex]

Explanation:

We are asked to find the potential energy of a bowling ball.

Potential energy is the energy an object possesses due to its position. It is calculated using the following formula.

[tex]E_p= mgh[/tex]

In this formula, m is the mass, g is the acceleration due to gravity, and h is the height.

The bowling ball has a mass of 2 kilograms. The hill is 5 meters high. Assuming this situation is occurring on Earth, the acceleration due to gravity is 9.8 meters per second squared.

Substitute the values into the formula.

[tex]E_p= (2 \ kg )(9.8 \ m/s^2)(5 \ m)[/tex]

Multiply the numbers together.

[tex]E_p=19.6 \ kg*m/s^2(5 \ m)[/tex]

[tex]E_p=98 \ kg*m^2/s^2[/tex]

Convert the units. 1 kilogram meter squared per second squared is equal to 1 Joule. Our answer of 98 kg*m²/s² is equal to 98 Joules.

[tex]E_p= 98 \ J[/tex]

The bowling ball has 98 Joules of potential energy.

The magnitude of the acceleration of the block is 3.5 [tex]\bold{m/s^2.}[/tex]

The correct option is (C) 3.5 [tex]\bold{m/s^2.}[/tex]

Acceleration is the rate of change of velocity with time.

By Newton’s Second law

This law establishes the relationship between the net applied force on an object with the resultant acceleration. For a constant magnitude of force, the more is the mass of the object, the lesser will be its acceleration.

Given,

The mass of the block is 2.0 kg.

The force in the horizontal direction on the block is [tex]\bold{4.0 N + 4.0 N \cos 40{}^\circ.}[/tex]

a is the acceleration in the horizontal direction.

The acceleration for the block can be determined using Newton’s Second law,

[tex]\begin{aligned} \Sigma F&=ma \\ F+F\cos 40{}^\circ &=ma \\ a&=\frac{F\left( 1+\cos 40{}^\circ \right)}{m} \\ &=\frac{4.0\text{ N}\left( 1.766 \right)}{2.0\text{ kg}} \\ &=3.5\text{ m/}{{\text{s}}^{2}} \end{aligned}[/tex]

Thus, the acceleration is 3.5 [tex]\bold{m/s^2.}[/tex]

Learn more about acceleration, here:

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Hi there!

Recall the conservation of momentum:

m1v1 + m2v2 = m1v1' + m2v2'

Let m1 = 5 kg ball and m2 = 10 kg ball

Since m2 is at rest, we can rewrite:

m1v1 = m1v1' + m2v2'

Plug in the given values:

5(2) = 5(-1) + 10v2'

Solve for v2':

10 = -5 + 10v2'

15 = 10v2'

15/10 = 1.5 m/s

We know that,

m1v1 + m2v2 = m1v1' + m2v2'

5 x 2 + 0 = 5 x -1 + 10 x v2'

10= -5 +10 x v2'

15 = 10 x v2'

v2' = 15/10

v2' = 1.5 m/s

hence , the speed of the larger ball after the collision will 1.5m/s

Answer:

Iron is correct answer. ... Since Magnet is also made up of Iron, Nickel and Cobalt. Therefore, it attracts iron towards it.

When a wave is transmitted from one substance to another, its refraction will change. Unless it reaches the second substance at a right angle, its direction will also change.

Refraction is the redirection of a wave as it passes from one medium to another medium. The redirection of wave can be caused by the wave's change in speed or by a change in the medium of wave.

The refraction of light or change in the direction of path of light in other medium occurs because the light wave travels with different speeds in different media. When a ray of light passes from one medium to another medium, the direction of the wave changes except for zero degrees because of the change in its speed.

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Answer:

Explanation:

Ignoring air resistance

1) from vertical rest

s = ½at²

t = √(2s/a)

t = √(2(80)/9.8)

t = 4.040610...

t = 4.0 s

2) d = vt

   d = 25(4.0)

   d = 100 m

3) v² = u² + 2as

   v² = 25² + 2(9.8)(80)

   v² = 2193

   v = 46.8294...

    v = 47 m/s

θ = - 90 + arcsin(25/46.8294)

θ = -57.7339...

θ = 58° below the horizontal

Answer:

I think it's a. Object velocity

Explanation:

.

Answer:

Object mass

Explanation:

I had answered and thats what it is

The distance the bus travelled in 20 seconds is 12.75 m

The first step is to write out parameters given in the question

Final velocity= 15

Initial velocity= 5

Time= 20

Distance= ?

V² + U²= 2as

15² + 5²= 2(9.8)s

225+25= 19.6s

250= 19.6s

s= 250/19.6

= 12.75

Hence the distance the bus travelled in 20 seconds is 12.75 m

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The models of the universe allow finding the result for how serious the universe in the distant future is:

The Big Bang model shows that the universe was created at a certain point and time where from which all matter is separating at a speed from these objects.

Based on these models and the measurements that the galaxies are moving away, in the distant future the galaxies must be very far from each other so that the universe would be composed of isolated entities without the possibility of interaction between them.

Within each galaxy the bodies are not separated because in each one there is a black body whose gravity holds the stars within its galaxy together.

In conclusion of the models of the universe we can find the result for how serious the universe in the distant future is:

Learn more about the motion of the galaxies here:  brainly.com/question/18212080

Please find attached photograph for your answer.

Hope it helps.

Do comment if you have any query.

Answer:

History in Perspective (education) HIP. Health Information Professional. HIP.

Explanation:

hope this helps

A ball swung around on a rope of a radius of 0.25 meters in a time of 0.40 seconds, then the velocity of the ball will be equal to 3.925 m/s.

Velocity is the rate of change of a traveling object's direction, as measured by a certain unit of time and as seen from a specific vantage point. Speed is a basic concept in kinematics, the branch of special relativity that studies how bodies move.

A scientific vector quantity called velocity must have both a magnitude and direction to be described.

As per the data provided in the question,

Radius, r = 0.25

Time, t = 0.40 seconds

Circumference of the circle, d = 2πr

d = 2π(0.25)

d = 1.570 m

Velocity, v = d / t

v = 1.570 / 0.40

v = 3.925 m/s.

Therefore, the velocity of the ball will be 3.925 m/s.

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Hi there!

To solve, we can use the following equation:

vf = vi + at

vi = initial velocity (m/s)

a = acceleration (m/s²)

t = time (s)

vf = final velocity (m/s)

Plug in the given values:

vf = 15 + 3(4)

vf = 15 + 12 = 27 m/s

Answer:

[tex]\boxed {\boxed {\sf 27 \ m/s}}[/tex]

Explanation:

We are asked to find the new or final velocity of a taxi.

We will use the following kinematic equation:

[tex]v_f=v_i+at[/tex]

The car was initially traveling at 15 meters per second. It accelerated at 3 meters per second squared for 4 seconds.

Substitute the values into the formula.

[tex]v_f= 15 \ m/s + (3 \ m/s^2* 4 \ s)[/tex]

Multiply the numbers in parentheses.

[tex]v_f= 15 \ m/s +12 \ m/s[/tex]

Add.

[tex]v_f=27 \ m/s[/tex]

The new velocity of the taxi is 27 meters per second.

Answer:

i can't tell which is left and right

Explanation:

Answer:

1. gravitational force = described as a field

2. Newton's First Law = a spacecraft cruising at v = constant with its rockets shut down

3. Copernican system =  an example of a heliocentric system

4. Kepler's First Law = the physical law that states that planetary orbits are ellipses

5. Kepler's Second Law = the physical law that states that equal areas are swept out in equal times

6. centripetal force = gravitational force that keeps planets in orbit

7. Kepler's Third Law = the physical law that states that R3\T2 = K for a system

8. geocentric system = the model of a planetary system that has the earth at the center

9. Newton's Third Law = the physical law nicknamed "action-reaction"

10. Newton's Second Law = the physical law that relates acceleration to net force

Answer:

B

Explanation:

Because Tolerance Is The Level Of Ability That Someone Has To Recognise And Help Others Values And Differences.

Answer:

Balanced forces acting on a stationary object cause the object to remain at rest. True: Forces can give energy to an object it acts on causing the object to change it state of motion. If forces acting on an object are balanced, they do not cause a change in motion.

Answer:

False

Explanation:

It is NOT possible for just three forces to be acting upon an object and they still balance each other. A free-falling object experiences a balance of forces.

The definition of the center of mass allows to find the result for the position of the mass center of more than the H₂O molecule is;

         [tex]x_{cm} = 0 \ and \ y_{cm} = 6.9 10^{-3 } nm[/tex]  

the concept of center of mass of a system is the point where external forces are applied, it is given by the expression

             [tex]\frac{x}{y} =\frac{1}{M_{total}} \sum m_i r_i[/tex]  

Where M is the total mass of the systemr_i and m_i sums the position and masses of the element i of the system

In the attachment we have a diagram of the system where the axis and coordinates of the molecules are shown, in this case it is indicated that the origin is in the oxygen atom, so its distance is zero.

           [tex]r_{cm} = \frac{1}{2 m + M} \ (2 m r )[/tex] )

They indicate the mass of the hydrogen atom m = 1.008 amu, the bond length r = 0.103 nm and there is an angle 106º between the two hydrogens, therefore the angle from the vertical is:

           θ = 106/2 = 53º

Let's find the position of the center of mass for each axis.

x-axis

           [tex]x_{cm} = \frac{1}{2m+ M} \ ( m x_1 - m x_2)[/tex]  

y-axis

          [tex]y_{cm} = \frac{1}{2m + M} \ ( m y_1 + m_2)[/tex]

Let's use trigonometry to find the components of the bond length.

         cos θ = [tex]\frac{y}{L}[/tex]  

         sin θ = [tex]\frac{x}{L}[/tex]  

         y = L cos θ

         x = L sin θ  

We substitute.

          [tex]x_{cm} = \frac{1}{2m+M} \ (mL (sin 53 + sin (-53)) \\y_{cm} = \frac{1}{2m + M} \ ( mL cos 53 + mL sin 53)[/tex]

we use.  

          sin θ = - sin -θ

          cos θ = cos -θ

Let's calculate.

        [tex]x_{cm} = 0 \\y_{cm} = \frac{1}{2 \ 1.008 + 15.9999} \ ( 2 \ 1.008 \ 0.103 cos 53)[/tex]

We see that the center of mass is on the x axis and at a distance from the y-axis of 6.9 10-3 nm

In conclusion using the definition of the center of mass we can find the result for the position of the center of mass of the H₂O molecule is;

          [tex]x_{cm}=0[/tex]  and [tex]y_{cm}[/tex]cm = 6.9 10⁻³ nm

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