4) While exploring the seafloor, you find that 100-million-year-old seafloor is 2000 kilometers
away from the ridge where it formed.
a) How fast is the plate moving away from the ridge in units of centimeters per year (cm/year)

The motor m applies a time-varying force of f (200 t) n, where t is in seconds. box b with mass 200 kg starts from rest, and the coefficients of kinetic and static friction are 0.2 and us 0.3 the acceleration due to gravity is g 9.8 m/s2 b 300 a) find the time ' when the box starts to move. b) calculate the speed of the crate at 3 s c) calculate the power delivered by the motor at t 3 s