Q1: An open container filled with water is moved vertically downward with a uniform linear acceleration. The pressure at its bottom will be

ANS:C - lesser than static pressure

1. Deceleration or Decreasing Velocity: When the container is moved downward but with a deceleration or decreasing velocity, the effective depth of the water column decreases due to the opposing force. As a result, the pressure at the bottom of the container can become lesser than the static pressure.
2. Opposing Force: If the container is decelerating, the effective "weight" of the water column diminishes, leading to a reduction in pressure at the bottom. The deceleration effectively counteracts the force of gravity to some extent, reducing the pressure experienced by the water at the bottom.
3. Dynamic Effects: In fluid dynamics, changes in velocity and acceleration can influence pressure gradients within the fluid. In cases of deceleration, dynamic effects may result in a pressure decrease relative to the static pressure.

Therefore, if the container is decelerating or moving downward with decreasing velocity, the pressure at the bottom of the container can be lesser than the static pressure. This condition is not as common as the pressure being greater, but it can occur under specific circumstances of motion and acceleration.