The velocity $v$ of a body moving along a straight line varies with time $t$ as $v=2 t^2 e^{-t}$, where $v$ is in $m / s$ and $t$ is in second. The acceleration of body is zero at $t=$
The velocity $v$ of a body moving along a straight line varies with time $t$ as $v=2 t^2 e^{-t}$, where $v$ is in $m / s$ and $t$ is in second. The acceleration of body is zero at $t=$
- A
$0$
- B
$2$
- C
$3$
- D
Both $(a)$ and $(b)$
Similar Questions
The maximum possible acceleration of a train moving on a straight track is $10\ m/s^2$ and maximum possible retardation is $5 \ m/s^2.$ If maximum achievable speed of train is $10\ m/s$ then minimum time in which train can complete a journey of $135\ m$ starting from rest and ending at rest, is.........$s$
The maximum possible acceleration of a train moving on a straight track is $10\ m/s^2$ and maximum possible retardation is $5 \ m/s^2.$ If maximum achievable speed of train is $10\ m/s$ then minimum time in which train can complete a journey of $135\ m$ starting from rest and ending at rest, is.........$s$
Give example of a motion where $x > 0$, $v < 0$, $a > 0$ at a particular instant.
Refer to the graph in figure. Match the following
Graph
Characteristics
$(A)$
$(i)$ has $v > 0$ and $a < 0$ throughout
$(B)$
$(ii)$ has $x > 0,$ throughout and has a point with $v = 0$ and a point with $a = 0$
$(C)$
$(iii)$ has a point with zero displacement for $t > 0$
$(D)$
$(iv)$ has $v < 0$ and $a > 0$
Refer to the graph in figure. Match the following
| Graph | Characteristics |
| $(A)$ | $(i)$ has $v > 0$ and $a < 0$ throughout |
| $(B)$ | $(ii)$ has $x > 0,$ throughout and has a point with $v = 0$ and a point with $a = 0$ |
| $(C)$ | $(iii)$ has a point with zero displacement for $t > 0$ |
| $(D)$ | $(iv)$ has $v < 0$ and $a > 0$ |
The distance-time graph of a particle at time $t$ makes angle $45^{\circ}$ with the time axis. After one second, it makes angle $60^{\circ}$ with the time axis. What is the average acceleration of the particle?
The distance-time graph of a particle at time $t$ makes angle $45^{\circ}$ with the time axis. After one second, it makes angle $60^{\circ}$ with the time axis. What is the average acceleration of the particle?