When the steel ball drops on the constant velocity cart, it follows a path in the frame of reference fixed to the , but a straight line in the frame of reference of the constant velocity cart. Without a fixed reference frame, one cannot tell whether or not you are in a frame of reference. All frames of reference moving at constant velocity with respect to one another are__equivilent__.

PARABOLIC, EARTH, VERTICAL, INERTIAL ang PHYSICAL LAWS

Explanation:

In this exercise you are asked to complete the missing words.

When the steel ball falls on the constant speed car, it follows a PARABOLIC path in the reference frame fixed to EARTH, but a VERTICAL straight line in the reference frame of the constant speed car. Without a fixed frame of reference, you cannot tell whether or not you are in an INERTIAL frame of reference. All frames of reference that move at constant speed relative to each other are PHYSICAL LAWS__equivilent__.

\ r

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it