A 1,000 kg car traveling 15.0 m/s brakes and comes to a stop after traveling 20.0 m. a. What is the car’s initial kinetic energy?
b. What is the car’s final kinetic energy?
c. How much work does it take to stop the car?
d. How much constant force is applied in bringing the car to a stop?

The volume of a gas is halved during an adiabatic compression that increases the pressure by a factor of 2.5. what is the specific heat ratio? show the math steps .

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?

In which of these cases are the two wave points considered to be in phase with each other?