The v-t graph of an object of mass 1,text{kg} | vedclass

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

Question

(D) According to the work-energy theorem,the net work done on an object is equal to the change in its kinetic energy: $W_{	ext{net}} = \Delta K = \fr

Vedclass · Accepted Answer

All of the above.

Vedclass · Answer

(D) According to the work-energy theorem,the net work done on an object is equal to the change in its kinetic energy: $W_{	ext{net}} = \Delta K = \frac{1}{2}m(v_f^2 - v_i^2)$.From the graph,the initial velocity at $t = 0\,	ext{s}$ is $v_i = 0\,	ext{m/s}$,and the final velocity at $t = 30\,	ext{s}$ is $v_f = 0\,	ext{m/s}$.Therefore,$W_{	ext{net}} = \frac{1}{2} 	imes 1 	imes (0^2 - 0^2) = 0\,	ext{J}$. Thus,statement $(A)$ is correct.Average acceleration is defined as $a_{	ext{avg}} = \frac{\Delta v}{\Delta t} = \frac{v_f - v_i}{t_f - t_i}$.Here,$v_f = 0\,	ext{m/s}$ and $v_i = 0\,	ext{m/s}$ over the interval $t = 0$ to $t = 30\,	ext{s}$.So,$a_{	ext{avg}} = \frac{0 - 0}{30 - 0} = 0\,	ext{m/s}^2$. Thus,statement $(B)$ is correct.Since $F_{	ext{avg}} = m 	imes a_{	ext{avg}}$ and $a_{	ext{avg}} = 0$,the average force $F_{	ext{avg}} = 1 	imes 0 = 0\,	ext{N}$. Thus,statement $(C)$ is correct.Since all statements are correct,the correct option is $(D)$.

The $v-t$ graph of an object of mass $1\,\text{kg}$ is shown. Which of the following statements is correct?

Similar Questions

$A$ car starts from rest and moves with a constant acceleration of $5 \,m/s^2$ for $10 \,s$ before the driver applies the brake. It then decelerates for $5 \,s$ before coming to rest. The average speed of the car over the entire journey is: (in $\,m/s$)

The driver of a bus moving with a velocity of $72 \ km/h$ observes a boy walking across the road at a distance of $50 \ m$ in front of the bus and decelerates the bus at $5 \ m/s^2$ by applying brakes and is just able to avoid an accident. The reaction time of the driver is (in $s$)

$A$ stone is dropped into a lake from a tower $500 \ m$ high. The sound of the splash will be heard by the man approximately after ..... $s$. (Take $g = 10 \ m/s^2$ and speed of sound $v = 340 \ m/s$)

What is reaction time? On what does the reaction time depend?

$A$ car is moving along a straight line,say $OP$ in the given figure. It moves from $O$ to $P$ in $18\; s$ and returns from $P$ to $Q$ in $6.0\; s$. What are the average velocity and average speed of the car in going from $O$ to $P$ and back to $Q?$

Vedclass Test Series

Exam Paper Generator

Online Exam Module