The velocity$-$time graph of an ascending passenger lift is as in the figure shown below
$(i)$ Identify the kind of motion of lift represented by lines $OA$ and $BC$.
$(ii)$ Calculate the acceleration of the lift
$(a)$ During the first two seconds.
$(b)$ Between the $3^ {r d}$ and $10^ {t h}$ second.
$(c)$ During the last two seconds.
The velocity$-$time graph of an ascending passenger lift is as in the figure shown below
$(i)$ Identify the kind of motion of lift represented by lines $OA$ and $BC$.
$(ii)$ Calculate the acceleration of the lift
$(a)$ During the first two seconds.
$(b)$ Between the $3^ {r d}$ and $10^ {t h}$ second.
$(c)$ During the last two seconds.
$(i)$ Motion is represented by lines $OA$ and $BC$ which are uniformly accelerated and uniformly retarded motion.
$(ii)$ The acceleration of the lift
$(a)$ During the first two seconds (from $OA)$
$a=\frac{(v-u)}{t}=\frac{4.6-0}{2}=2.3 m s ^{-2}$
$(b)$ Between third and tenth second, the graph is a straight line parallel to the time axis. Hence, motion is uniform, acceleration $=0$
$(c)$ During the last two seconds (from $BC$)
$a=\frac{(v-u)}{t}=\frac{0-4.6}{12-10}=\frac{-4.6}{2}=-2.3 m s ^{-2}$
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$(a)$ Define acceleration.
$(b)$ A stone describes a circular path with a constant speed. State the type of motion of the stone.
$(a)$ Define acceleration.
$(b)$ A stone describes a circular path with a constant speed. State the type of motion of the stone.
A truck is moving on a straight road with uniform acceleration. The following table gives the speed of the truck at various instants of time.
Speed $\left(m s^{-1}\right)$
$5$
$10$
$15$
$20$
$25$
$30$
Time $(s)$
$0$
$10$
$20$
$30$
$40$
$50$
Draw the speed-time graph by choosing a convenient scale. Determine from it
$(i)$ the acceleration of truck
$(ii)$ the distance travelled by the truck in $50$ seconds.
A truck is moving on a straight road with uniform acceleration. The following table gives the speed of the truck at various instants of time.
| Speed $\left(m s^{-1}\right)$ | $5$ | $10$ | $15$ | $20$ | $25$ | $30$ |
| Time $(s)$ | $0$ | $10$ | $20$ | $30$ | $40$ | $50$ |
Draw the speed-time graph by choosing a convenient scale. Determine from it
$(i)$ the acceleration of truck
$(ii)$ the distance travelled by the truck in $50$ seconds.
Draw velocity-time graphs for the following situations
$(i)$ When body is moving with uniform velocity.
$(ii)$ When body is moving with variable velocity, but uniform acceleration.
$(iii)$ When body is moving with variable velocity, but uniform retardation.
$(iv)$ When body is moving with a variable velocity and variable acceleration.
Draw velocity-time graphs for the following situations
$(i)$ When body is moving with uniform velocity.
$(ii)$ When body is moving with variable velocity, but uniform acceleration.
$(iii)$ When body is moving with variable velocity, but uniform retardation.
$(iv)$ When body is moving with a variable velocity and variable acceleration.
An electron moving with a velocity of $5 \times 10^{4}\, ms ^{-1}$ enters into a uniform electric field and acquires a uniform acceleration of $10^{4}\, ms ^{-2}$ in the direction of its initial motion.
$(i)$ Calculate the time in which the electron would acquire a velocity double of its initial velocity.
$(ii)$ How much distance the electron would cover in this time ?
An electron moving with a velocity of $5 \times 10^{4}\, ms ^{-1}$ enters into a uniform electric field and acquires a uniform acceleration of $10^{4}\, ms ^{-2}$ in the direction of its initial motion.
$(i)$ Calculate the time in which the electron would acquire a velocity double of its initial velocity.
$(ii)$ How much distance the electron would cover in this time ?