An object with a mass $10 \,kg$ moves at a constant velocity of $10 \,m/sec$. A constant force then acts for $4\, second$ on the object and gives it a speed of $2\, m/sec$ in opposite direction. The acceleration produced in it, is ........ $m/{\sec ^2}$
$3$
$ - 3$
$0.3$
$ - 0.3$
Acceleration versus time graph of a body starting from rest is shown in the figure. The velocity versus time graph of the body is given by
If the speed of moving object decreases, then give direction of velocity and acceleration.
Give important factor to control the speed of vehicle in area of school or hospital.
Displacement $(x)$ of a particle is related to time $(t)$ as:
$x = at + bt^2 -ct^3$
where $a, b$ and $c$ are constants of the motion. The velocity of the particle when its acceleration is zero is given by
A person sitting in a moving train with his face towards the engine, throws a coin vertically upwards. The coin falls ahead of person. The train: