Newton’s Second Law of Motion describes the relationship of force, mass and acceleration using the mathematical equation f = ma. A stack of ten pennies has a mass of 25 grams and is sitting at rest. How many Newtons of force would have to be applied to get the stack accelerating to 0.25 m/s2? (Include the unit of measurement, Newtons, in your answer)

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?