Question

1. Write a description of all Newton’s Law, including any equations associated. For each law, provide a real-life example.

Answer 1

Newton’s 1st Law of Motion: The law of Inertia

Statement: A body remains at rest, or moves in a straight line (at a constant velocity), unless acted upon by a net outside force.

Real life application – Shake up that bottle of ketchup! When you shake that bottle, you bring the bottom down, then suddenly you stop. This is inertia and it’s the inertia which causes the ketchup to come out of the bottle.

Newton’s 2nd Law of Motion: F = ma

Statement: The acceleration of an object is proportional to the force acting upon it.

Real life application – Your friend weighs less than you, but you both walk exerting the same amount of force. Your friend will go a good deal faster than you because the acceleration used by them would undoubtedly be higher.
One of the main reasons why people constantly try to reduce the mass of objects is to be able to increase its speed and acceleration. All of the factors have an effect on each other. If something has much more mass, then exerting more force will make it move faster.

Newton’s 3rd Law: Equal and opposite reaction

Statement: For every action, there is an equal and opposite reaction. If one body exerts force on the second body then the second body exerts equal force on the first body.

Real life application – Hitting the Wall with Your Fist
There are two forces, your force and the other is an equal and opposite force applied by the wall on the fist. Hence, the harder you hit the wall the more force is exerted on your fist by the wall. This is why you get hurt more.