"The uniform motion is possible when no frictional forces oppose" is the concept of

$A$ 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 .......... $N$.

When a train stops suddenly,passengers in the running train feel an instant jerk in the forward direction because

Physical independence of force is a consequence of

For ordinary terrestrial experiments,the observer in an inertial frame in the following cases is

$A$ stone tied to the end of a string is whirled in a circular path. Why does the stone move in the direction of the tangent at that point when the string breaks?