A block of mass 2 kg placed on a long frictionless horizontal table is pulled horizontally by a constant force F. It is found to move 10 m in the first two seconds. Find the magnitude of F.

A particle is observed from two frames S₁ and S₂. The frame S₂ moves with respect to S₁ with an acceleration a. Let F₁ and F₂ be the pseudo forces on the particle when seen from S₁ and S₂ respectively. Which of the following are not possible?

A person says that he measured the acceleration of a particle to be nonzero while no force was acting on the particle.

A car moving at 40 km/h is to be stopped by applying brakes in the next 4.0 m. If the car weighs 2000 kg, what average force must be applied on it?

In a TV picture tube electrons are ejected from the cathode with negligible speed and reach a velocity of 5 × 10⁶ m/s in travelling one centimeter. Assuming straight line motion, find the constant force exerted on the electron. The mass of the electron is 9.1 × 10^-31 kg.