To open a soda can lid, you can apply a force of 50 N to a car key wedged under the lid. The car key applies a force of 390 N to the lid. What is the mechanical
advantage of using the car key to open the can lid?

7.8

Explanation:

Here, an effort of 50 N is applied at the car key and overcomes the resistance(or load) of 390 N at the lid.

mechanical advantage

=load/effort

=390 N/50 N

=7.8

the moon affects the earth gravitation ally, causing certain motions of that body and also producing tides in its ocean and atmosphere. the tidal wave in our atmosphere is, however, far too minute to be an effective cause in any known meteorological phenomenon.

explanation:

v=ir = 3x15 =45 v