the odometer of a car reads 68420 km when the clock shows the time 9 am if at 9 30 am the odometer reading has changed to 68540 calculate the speed of the car in km/min during this time

Why is there friction between objects

Aregion of space in which a measurable gravitational force is indicated by the force exerted on a test mass is called

Arotating space station is said to create “artificial gravity”—a loosely-defined term used for an acceleration that would be crudely similar to gravity. the outer wall of the rotating space station would become a floor for the astronauts, and centripetal acceleration supplied by the floor would allow astronauts to exercise and maintain muscle and bone strength more naturally than in non-rotating space environments. if the space station is 200 m in diameter, what angular velocity would produce an “artificial gravity” of 9.80 m/s^{2} 2 at the rim?