As you slide a heavy box across the floor, friction applies a force of -100 N over a distance of 5 m. How much work is done by friction?
A. -500 J
B. -20 j
C. -100 J
D. -95 J

Atrain departs from its station at a constant acceleration of 5 m/s. what is the speed of the train at the end of 20s?

Calculate the amount of heat produced when 18000 coulombs of charge is transferred in one hour through a potential difference of 50v

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?