Inelastic collisions Quiz 1

Question 1

A boy observes two particles colliding on a horizontal surface and sticks together after colliding with each other, after observation he gave some observations regarding energy, the correct statements given by him will be-

Accepted Answer

both (b) and (c)

Answer

Kinetic energy will be conserved.

Answer

energy is conserved.

Answer

work done is negative.

Question 2

Ram having two balls of mass $$5\,kg$$ each, to perform a collision between them he places a ball at rest and lets the other ball hit it with some kinetic energy $$E$$. If the final combined kinetic energy of two balls is $$75\ %$$ of original kinetic energy. The coefficient of restitution $$e$$ will be equal to $$\$$<img  src="https://cmds-vedantu.s3.ap-southeast-1.amazonaws.com/prod/question-sets/02600974-2336-482f-8f71-bf8f433402a9111547345954834544.png"/>

Accepted Answer

$$\dfrac{1}{\sqrt{2}}$$

Answer

$$\dfrac{1}{2}$$

Answer

$$\dfrac{1}{\sqrt{3}}$$

Answer

Both (a) or (b)

Question 3

A man throws a ball towards a wall with a velocity of $$4\hat{i}+6\hat{j}$$. The coefficient of restitution between wall and ball is 1/4 . The final velocity vector calculated by the man after the impact will be-

Accepted Answer

$$-\hat{i}+6 \hat{j}$$

Answer

$$\hat{i}+6 \hat{j}$$

Answer

$$\hat{i}+4 \hat{j}$$

Answer

$$-\hat{i}-4 \hat{j}$$

Question 4

A box of mass $$2\,kg$$ is attached to a ceiling with weightless string as shown in figure. A boy at the ground throws a small stone of mass $$1\,kg$$ so that it hits a block with a speed of $$5\,m/s$$ and stick to it, the final speed of combined system of block + stone will be- <img  src="https://cmds-vedantu.s3.ap-southeast-1.amazonaws.com/prod/question-sets/77c1f569-0080-4810-958c-3cbfb3f6363c8608580713046343753.png"/>

Accepted Answer

$$\dfrac{5}{3}m/s$$

Answer

$$\dfrac{1}{2}m/s$$

Answer

$$\dfrac{2}{3}m/s$$

Answer

$$\dfrac{3}{2}m/s$$

Question 5

A basketball player drops the ball from a height of $$5\,m$$ which collides with ground and rebounds and again reaches some height $$H$$, the coefficient of restitution is $$0.7$$. The value of $$H$$ calculated by the player will be-

Accepted Answer

2.45 m

Answer

3.45 m

Answer

1.55 m

Answer

6.5 m