Kinetic energy Quiz 1

Question 1

A bullet having velocity $$''V''$$ strikes a piece of wood of thickness $$''t''$$. After crossing the thickness, velocity remains one fourth of the initial. Find retarding force offered by wood. $$ \ $$<img  src="https://cmds-vedantu.s3.ap-southeast-1.amazonaws.com/prod/question-sets/b53ed41a-abfe-4d78-b547-0ba4fab3a95c4185566791329934111.png"/>

Accepted Answer

$$\dfrac{15}{32}\dfrac{m{{v}^{2}}}{t}$$

Answer

$$\dfrac{15}{16}\dfrac{m{{v}^{2}}}{t}$$

Answer

$$\dfrac{3}{8}\dfrac{m{{v}^{2}}}{T}$$

Answer

$$\dfrac{3}{8}\dfrac{m{{v}^{2}}}{t}$$

Question 2

A man-sized ball of mass $$"m"$$ is thrown vertically upward with a velocity of $$\sqrt{gH}$$ from a building of height $$"H"$$. The provided kinetic energy just before impact with the ground is

Accepted Answer

$$mgH$$

Answer

$$3mgH$$

Answer

$$4mgH$$

Answer

$$8mgH$$

Question 3

A man-made block of mass $$m=1\,kg$$ with an initial velocity of $$v=10\,m/s$$, is allowed to slide over a rough surface with a coefficient of friction of $$\mu =0.1$$. Because of friction, it comes to a halt after $$T\sec $$. The distance travelled by block arriving at a rest is

Accepted Answer

$$50\,m$$

Answer

$$100\,m$$

Answer

$$25\,m$$

Answer

$$12.5\,m$$

Question 4

A ball of man $$''m''$$ moving with velocity $${{V}}$$ in horizontal direction strikes another hall of man $$''2m''$$ resting over the surface elastically. The loss in kinetic energy is

Accepted Answer

$$67\%$$

Answer

$$50\%$$

Answer

$$33\%$$

Answer

$$75\%$$

Question 5

Velocity time graph shows the variation in velocity with respect to time. According to graph the kinetic energy of particle is<img  src="https://cmds-vedantu.s3.ap-southeast-1.amazonaws.com/prod/question-sets/a5c51d46-e4eb-486d-858d-b8da5b48bb138407407110226058087.png"/>

Accepted Answer

decreasing with time

Answer

increasing with time

Answer

constant throughout

Answer

none of above