Two monkeys with the same mass stand on a bra | vedclass

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

Question

(C) According to the Work-Energy Theorem,the total work done on an object is equal to the change in its kinetic energy: $W = \Delta K = K_f - K_i$.Sin

Vedclass · Accepted Answer

$W_A = W_B, v_A = v_B$

Vedclass · Answer

(C) According to the Work-Energy Theorem,the total work done on an object is equal to the change in its kinetic energy: $W = \Delta K = K_f - K_i$.Since both monkeys start from rest at the same height $h$,their initial kinetic energy $K_i = 0$ is the same.Both monkeys hit the floor at the same final height (zero),so their final kinetic energy $K_f$ depends only on the change in potential energy,which is $\Delta U = mgh$ for both.For monkey $B$,the only force doing work is gravity,so $W_B = \Delta K_B = mgh$.For monkey $A$,the forces acting are gravity and the tension in the rope. The tension acts perpendicular to the displacement during the swing,so it does zero work. When monkey $A$ lets go,it is in free fall. Thus,the total work done on monkey $A$ is also $W_A = mgh$.Since $W_A = W_B$,both monkeys have the same change in kinetic energy,and since they start from rest,they have the same final kinetic energy $K_f = mgh$.Therefore,their final speeds $v = \sqrt{2gh}$ are also equal: $v_A = v_B$.

Similar Questions

$A$ chain of length $L$ and mass $m$ is placed upon a smooth surface as shown. The length of the chain on the incline is $b$. Calculate the velocity of the chain when its end reaches point $B$.

$A$ ball at rest is dropped from a height of $12 \,m$. It loses $25 \%$ of its kinetic energy on striking the ground and bounces back to a height '$h$'. Then the value of '$h$' is (in $\,m$)

$A$ car comes to rest after traveling a distance $s$ under a constant retarding force $F$. If the mass of the car is increased by $50\%$,at what distance will the car come to rest,assuming the same retarding force $F$ and initial velocity $v$?

Work equal to $25\,J$ is done on a mass of $2\,kg$ to set it in motion. If the whole of it is used to increase the kinetic energy,then the velocity acquired by the mass is ............ $m/s$.

$A$ force acts on a $3\, g$ particle in such a way that the position of the particle as a function of time is given by $x = 3t - 4t^2 + t^3$,where $x$ is in $meters$ and $t$ is in $seconds$. The work done during the first $4\, seconds$ is ................. $mJ$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module