Inertia is that property of a body by virtue of which the body is

Explain the difference between mass and weight.

$A$ body of mass $2 \, kg$ is sliding with a constant velocity of $4 \, m/s$ on a frictionless horizontal table. The force required to keep the body moving with the same velocity is .......... $N$.

What was the mistake in Aristotle's idea regarding motion?

$A$ person is sitting in a travelling train and facing the engine. He tosses up a coin and the coin falls behind him. It can be concluded that the train is

$A$ trolley of mass $300 \; kg$ carrying a sandbag of $25 \; kg$ is moving uniformly with a speed of $27 \; km/h$ on a frictionless track. After a while,sand starts leaking out of a hole on the floor of the trolley at the rate of $0.05 \; kg \cdot s^{-1}$. What is the speed (in $km/h$) of the trolley after the entire sandbag is empty?