The picture above illustrates the horizontal forces acting on a car. The car’s engine force pushes forward, while friction between the tires and the road, along with wind resistance drag at the car in the backwards direction. Which of the following must be true about these forces if the car is driving forward on a level road at a constant speed of 45 miles per hour?

Cyclotrons are widely used in nuclear medicine for producing short-lived radioactive isotopes. these cyclotrons typically accelerate h- (the hydride ion, which has one proton and two electrons) to an energy of 5 mev to 20 mev. this ion has a mass very close to that of a proton because the electron mass is negligible—about 1 2000 of the proton’s mass. a typical magnetic field in such cyclotrons is 1.9 t. (a) what is the speed of a 5.0-mev h-? (b) if the h- has energy 5.0 mev and b = 1.9 t, what is the radius of this ion’s circular orbit?

Earth has a mass of 5.97 x 1024kg, and a mean radius of 6.38 x 106m. what would be the orbital speed and period of a satellite in orbit 1.44 x 108 m above earth?

Arock thrown straight up takes 4.2 s to reach its maximum height what was its initial velocity