Ask question

Ask question

All categories

3 years ago

14

a metal sphere with a mass of 90 kg rolls along at 16m/s and strikes a stationary sphere having a mass of 140kg. the first spher

e stops completely. at what speed does the second sphere move away at?

1 answer:

baherus [9]3 years ago

7 0

13.2 meters per second

You might be interested in

A 77.0−kg short-track ice skater is racing at a speed of 12.6 m/s when he falls down and slides across the ice into a padded wal

sukhopar [10]

Answer:

-6112.26 J

Explanation:

The initial kinetic energy, $KE_i$ is given by

$KE_i=0.5mv_1^{2$ } where m is the mass of a body and $v_i$ is the initial velocity

The final kinetic energy, $KE_f$ is given by

$KE_f=0.5mv_f^{2}$ where $v_f$ is the final velocity

Change in kinetic energy, $\triangle KE$ is given by

$\triangle KE=KE_f-KE_i=0.5mv_f^{2}-0.5mv_1^{2}=0.5m(v_f^{2}-v_i^{2})$

Since the skater finally comes to rest, the final velocity is zero. Substituting 0 for $v_f$ and 12.6 m/s for $v_i$ and 77 Kg for m we obtain

$\triangle KE=0.5*77*0^{2}-0.5*77*(0^{2}-12.6^{2})=-6112.26 J$

From work energy theorem, work done by a force is equal to the change in kinetic energy hence for this case work done equals <u>-6112.26 J</u>

3 0

3 years ago

Can someone check if these are correct?? It’s a big part of my grade, there’s more questions at the bottom but I’ll just show th

Andrei [34K]

Yes it it if u need the last 3 I can help

6 0

3 years ago

Read 2 more answers

A roller coaster has a vertical loop with radius 25.7 m. With what minimum speed should the roller-coaster car be moving at the

gogolik [260]

Answer:

15.88m/s

Explanation:

At the top of the roller coaster you will have three forces acting on the roller-coaster. See the image below. Fc is the centripetal force (for an object in circular motion), Fg is the gravitational force, and Fn is the normal force. To achieve the minimum speed we assume the roller-coaster is barely touching the vertical loop and so the normal force is zero. This leaves two acting forces.

$F_g = F_c\\mg = \frac{m\times v^2}{r}\\v = \sqrt{gr} = \sqrt{9.81 \times 25.7} = 15.88 m/s$

7 0

3 years ago

Two carts, A and B, are connected by a spring and sitting at rest on a track. Cart A has a mass of 0.4 kg and Cart B has a mass

Ilya [14]

Both carts experience the same force but Cart A has a greater speed after the recoil.

The given parameters;

<em>Mass of the cart A = 0.4 kg</em>
<em>Mass of the cart B = 0.8 kg</em>

Apply the principle of conservation of linear momentum to determine the velocity of the carts after collision;

$m_Av_0_A\ + m_Bv_0_B = m_Av_f_A \ + m_Bv_f_B\\\\the \ initial \ velocity \ of \ both \ carts = 0\\\\0.4(0) + 0.8(0) = 0.4v_f_A + 0.8v_f_B\\\\0 = 0.4v_f_A + 0.8v_f_B\\\\0.4v_f_A = -0.8v_f_B\\\\v_f_A= \frac{-0.8 v_f_B}{0.4} \\\\v_f_A = - 2 \ v_f_B \ \ m/s$

According to Newton's third law of motion, action and reaction are equal and opposite. The force exerted on cart A is equal to the force exerted on cart B but in opposite direction.

$F_A = -F_B$

Thus, the correct statement that compares the motion and forces acting on the two carts is "Both carts experience the same force but Cart A has a greater speed after the recoil."

Learn more about conservation of linear momentum here: brainly.com/question/7538238

6 0

2 years ago

After running for a while, the fan becomes hot to the touch, and ever so often releases ___________________ energy into the air.

kykrilka [37]

Answer:

thermal

Explanation:

4 0

3 years ago