A body falls freely onto a hard horizontal su | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) Let the initial height from which the body falls be $H_0$. When a body falls from height $H_0$,its velocity just before the first impact is $v_0 =

Vedclass · Accepted Answer

$256: 625$

Vedclass · Answer

(A) Let the initial height from which the body falls be $H_0$. When a body falls from height $H_0$,its velocity just before the first impact is $v_0 = \sqrt{2gH_0}$. After the first impact,the velocity becomes $v_1 = e v_0$,and the height reached is $H_1 = e^2 H_0$. After the second impact,the velocity becomes $v_2 = e v_1 = e^2 v_0$,and the height reached is $H_2 = e^4 H_0$. Given $e = 0.8 = 4/5$. The ratio of the height after the second impact to the initial height is $H_2 / H_0 = e^4$. Calculating $e^4 = (0.8)^4 = (4/5)^4 = 256 / 625$. Thus,the ratio is $256: 625$.

$A$ body falls freely onto a hard horizontal surface. If the coefficient of restitution between the surface and the body is $e = 0.8$,then the ratio of the maximum height to which the body rises after the second impact to the initial height of the body is:

Similar Questions

If a body collides inelastically with another body of the same mass initially at rest,what will be the ratio of their speeds after the collision?

$A$ lead ball of mass $2 \ kg$ moving with a velocity of $1.5 \ ms^{-1}$ collides with a ball of mass $3 \ kg$ at rest. After the collision,the second ball moves with a velocity of $1 \ ms^{-1}$ in the original direction of motion of the first ball. Find $\Delta KE$ in $J$.

$A$ ball is thrown with a velocity of $6\, m/s$ vertically downwards from a height $H = 3.2\, m$ above a horizontal floor. If it rebounds back to the same height,then the coefficient of restitution $e$ is $[g = 10\, m/s^2]$.

$A$ body falls on a surface with a coefficient of restitution of $0.6$ from a height of $1 \, m$. The body rebounds to a height of ........... $m$.

$A$ ball strikes a smooth horizontal ground at an angle of $45^o$ with the vertical. What cannot be the possible angle of its velocity with the vertical after the collision? (Assume $e \leq 1$ ).

Vedclass Test Series

Exam Paper Generator

Online Exam Module