Arunner taking part in the 200 m dash must run around the end of a track that has a circular arc with a radius of curvature of 45 m. the runner starts the race at a constant speed. if she completes the 200 m dash in 21.6 s and runs at constant speed throughout the race, what is the magnitude of her centripetal acceleration (in m/s2) as she runs the curved portion of the track?

The law of the conservation of momentum says that the total momentum of any closed and isolated system cannot

Acharge q experiences no net force at a particular point in space. which of the following situations described below must always be true? -there are no other charges nearby. -if there are other charges nearby, they must all have the same sign as q. -if there are other charges nearby, they must all have the opposite sign of q. -if there are other charges nearby, the total positive charge must equal the total negative charge. -none of the above

If you let go of the notebook after lifting it, will it move? how?