An electromagnet is strong enough to lift 200 kg of mass. If you double the number of turns of wire around the core and triple the current, how much will it be able to lift?

Magnetic field is proportional to NIA.

N is the number of turns, I is the current and A is the area

You see N=2n, I = 3 i. Therefore, it will 6 times stronger

200*6= 1200 kg. It can lift now is 1200 kg.

another example of kinetic energy would be,

kinetic energy   >     moving energy

answer   >   letter choice (c),   a hammer falling off a table.

hope that !                                         : )

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.