A Speedster car is traveling at a constant speed of 30m/s when it passes a stationary police car. one second after the car passes the police car
Start from rest and accelerates at a constant rate of 7,50 m/s to chase the speeding car. How long afterwards will the police
car catch up with the speeding car?

Aray of light traveling parallel to the principal axis of a concave mirror will be reflected through the mirror's

Consider an ordinary, helium-filled party balloon with a volume of 2.2 ft3. the lifting force on the balloon due to the outside air is the net resultant of the pressure distribution exerted on the exterior surface of the balloon. using this fact, we can derive archimedes’ principle, namely that the upward force on the balloon is equal to the weight of the air displaced by the balloon. assuming that the balloon is at sea level, where the air density is 0.002377 slug/ft3, calculate the maximum weight that can be lifted by the balloon. note: the molecular weight of air is 28.8 and that of helium is 4.

Polly is pushing a box across the floor with a force of 30 n. the force of gravity is –8 n, and the normal force is 8 n. which value could describe the force of friction if polly could not move the box?