A 60kg teen girl is riding a merry-go-round with a radius of 6m. What is the centripetal force on the boy if his velocity is 10 m/s

Glass has a hardness that is in the middle of the hardness scale. what is the hardness of glass?

The energy equivalent of the rest mass of an electron is

The magnitude of the magnetic field at a certain distance from a long, straight conductor is represented by b. what is the magnitude of the magnetic field at twice the distance from the conductor? a. at twice the distance, the magnitude of the field is 4b.b. at twice the distance, the magnitude of the field is 2b.c. at twice the distance, the magnitude of the field is b/2.d. at twice the distance, the magnitude of the field is b/4.e. at twice the distance, the magnitude of the field remains equal to b.