A 461g wood block is given a quick push across a table. During the push it accelerates at a rate of 0.47m/s2, but after the push it slows to a stop with an acceleration of -0.59m/s2. Assuming the frictional force was the same strength both during and after the push, what was the strength of the force used to push the block to start with?

Samir watches a 100-minute movie on his spaceship. maria's spaceshipe flies in the same direction as samir's spaceship but she observes his move to last 125 minutes and his spaceship to be 40 m long. how long does samir observe his own spaceship to be? according to an observer on earth, planet x is stationary. maria and samir depart earth on their spaceships at the same time, each flying at 0.5c. maria flies toward planet x and samir flies in the opposite direction. according to maria, her voyage to planet x takes 9 years. how many years does marias voyage take according to samir?