You wish to push a cart across a friction less surface, so you apply a 20 N force for a period of 3 seconds. As a result, the
cart goes from rest to a velocity of 2.3 m/s. What is the mass of
the cart?

Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. the scale reads 830 n for the first 2.4 s after the elevator starts moving, then 930 n for the next 2.4 s. part a what is the elevator's speed 4.8 s after starting? express your answer with the appropriate units.