A weightlifter lifts 240 ,kg from the ground | vedclass

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

Question

(B) The work done $(W)$ by the weightlifter is equal to the change in potential energy,given by $W = mgh$.Here,mass $(m)$ = $240 \,kg$,height $(h)$ =

Vedclass · Accepted Answer

$1960 \,W$

Vedclass · Answer

(B) The work done $(W)$ by the weightlifter is equal to the change in potential energy,given by $W = mgh$.Here,mass $(m)$ = $240 \,kg$,height $(h)$ = $2.5 \,m$,and acceleration due to gravity $(g)$ = $9.8 \,m/s^2$.$W = 240 	imes 9.8 	imes 2.5 = 5880 \,J$.The time taken $(t)$ = $3 \,s$.Average power $(P)$ is defined as the rate of doing work,$P = W / t$.$P = 5880 / 3 = 1960 \,W$.Therefore,the average power is $1960 \,W$.

$A$ weightlifter lifts $240 \,kg$ from the ground to a height of $2.5 \,m$ in $3 \,s$. The average power is:

Similar Questions

$A$ block of mass $5 \,kg$ is lying on a frictionless table. $A$ force of $20 \,N$ is applied on it for $10 \,s$. Calculate its kinetic energy. (in $J$)

Is it possible that an object is in a state of accelerated motion due to an external force acting on it,but no work is being done by the force? Explain with an example.

The work done by a force on a body will be positive if the:

Justify,giving proper reasoning,whether the work done in the following case is positive or negative: Work done by friction on a body sliding down an inclined plane.

How much work should be done on an object of $120 \, kg$ to increase its speed from $25 \, m s^{-1}$ to $40 \, m s^{-1}$ (in $, J$)?

Vedclass Test Series

Exam Paper Generator

Online Exam Module