Answer to Question #63384 in Physics for Maria

Question

3. If you try and push your friend. What happens if he pushes back?
Or
4. You need more force to move and accelerate heavier objects than lighter objects

Which law is applicable on both condition of newtons law of motion?

Answer 1

Newton's second law states:
Acceleration is produced when a force acts on a mass. The greater the mass (of the object being accelerated) the greater the amount of force needed (to accelerate the object).
If you push your friend hard enough, which means you exert force on your friend, he will start moving away from you.
You need more force to move and accelerate heavier objects than lighter objects - just because the 2nd law states that force required to produce acceleration is directly proportional to the object mass.