Work done in time t on a body of mass m which is accelerated from rest to a speed v in time t₁ as

English

Gujarati

Hindi

5.Work, Energy, Power and Collision

normal

Work done in time $t$ on a body of mass $m$ which is accelerated from rest to a speed $v$ in time $t_1$ as a function of time $t$ is given by

A

$\frac{1}{2}m\,\frac{v}{{{t_1}}}{t^2}$

B

$m\,\frac{{{v}}}{{{t_1}}}{t^2}$

C

$\frac{1}{2}{\left( {\,\frac{{mv}}{{{t_1}}}} \right)^2}{t^2}$

D

$\frac{1}{2}m\,\frac{{{v^2}}}{{{t^2}_1}}{t^2}$

Solution

Work done $=F \times s$

$=m a \times \frac{1}{2} a t^{2}\left[\text {Fromx}=u t+\frac{1}{2} a t^{2}\right]$

$\therefore W=\frac{1}{2} m a^{2} t^{2}=\frac{1}{2} m\left(\frac{v}{t_{1}}\right)^{2} t^{2}\left[A s a=\frac{v}{t_{1}}\right]$

Standard 11

Physics

Share

Similar Questions

Work done in time $t$ on a body of mass $m$ which is accelerated from rest to a speed $v$ in time $t_1$ as a function of time $t$ is given by

normal

A bullet of mass $m$ moving with velocity $v$ strikes a block of mass $M$ at rest and gets embedded into it. The kinetic energy of the composite block will be

normal

A simple pendulum of mass $200\, gm$ and length $100\, cm$ is moved aside till the string makes an angle of $60^o$ with the vertical. The kinetic and potential energies of the bob, when the string is inclined at $30^o$ to the vertical, are

normal

A block of mass m initially at rest is dropped from a height $h$ on to a spring of force constant $k$. the maximum compression in the spring is $x$ then

normal

A rifle bullets loses $\left(\frac{1}{20}\right)^{th}$ of its velocity in passing through a plank. Assuming that the plank exerts a constant retarding force, the least number of such planks required just to stop the bullet is ………….

normal