B. A book sitting on a shelf. The books force is going down while the shelf's force is moving up against the book at an equal force.The answer would be B.
It is Potential energy it's at rest
Answer:
A magnet is used in a compass to show the direction.
Magnets are used in medical equipment.
Powerful magnets are used to lift objects
they are used in refrigerator, televisions, earphones etc
Mass of the object m = 25 kg
Coefficient of friction Uk = 0.15
Frictional force Ff = Uk x F => Ff = Uk x m x g
Ff = 0.15 x 25 x 9.8
Frictional Force Ff = 36.75 N