If the coils of an electromagnet are placed inside a set of secondary coils, what has to happen to create a current in the secondary coils? a.
The current in the electromagnet must be zero.

b.
The current in the electromagnet must be constant (but not zero).

c.
The current in the electromagnet must be constant (or zero).

d.
The current in the electromagnetic must be increasing or decreasing - changing and not steady.

a.   mass number from atomic number

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.

the answer is c. the lower legs are levers, and the knees are fulcrums. the ankles hold the loads.