A force of F = (5y + 20)ĵ N acts on a particle. The work done by this force when the particle is moved from y = 0 m to y = 10 m is:

A body of mass 20 kg has its speed reduced from 30 km/h to 15 km/h in 4.0 seconds. Calculate the magnitude of change in its kinetic energy (rounded to the nearest integer).

A person lifts 5 kg of potatoes from the ground floor to a height of 4 m to bring them to the first floor. Taking g = 9.8 m/s2, calculate the work done.