$A$ cork is submerged in water by a spring attached to the bottom of a bowl. When the bowl is kept in an elevator moving with an acceleration $a$ downwards, the length of the spring:

$A$ plumb bob is hanging from the ceiling of a car. If the car moves with an acceleration $a$,the angle made by the string with the vertical is

Select the correct statement regarding pseudo force.

If the rope of a lift breaks suddenly,what is the tension exerted by the floor of the lift on a person inside? ($a =$ acceleration of the lift)

$A$ simple pendulum is attached to a block which slides without friction down an inclined plane $ABC$ having an angle of inclination $\alpha$ as shown below. While the block is sliding down,the pendulum oscillates in such a way that at its mean position,the direction of the string is

$A$ lift is accelerating downward with an acceleration $a$. $A$ man inside the lift throws a ball upward with an acceleration $a_0$ relative to the lift $(a_0 < a)$. What is the acceleration of the ball as observed by an observer on the Earth?