Newton’s First Law of Motion: Newton’s first law of motion states that an object that is in motion will remain in motion unless acted upon by an outside force. Video 2018-04-18, 10 17 52 PM-1v4l94a In this video, a blue ball rolls across a table until it collides with a yellow ball. Both balls start in motion towards each other but when they collide, they stop moving in that direction and start going the other way. The balls are both forces opposing each other. This shows how objects change velocity when force is applied to them as well as a demonstration of Newton’s Third Law of Motion. The force that is always acting on virtually every object in the universe would be the force of gravity so practically everything is always having force applied to it, but far away from celestial bodies, the influence that gravity has can be almost negligible.
Newton’s Second Law of Motion: Newton’s second law of motion states that the net force an object exerts is a product of mass of the object and its acceleration. Net force is the amount of unbalanced force acting on an object. An unbalanced force is a force that is not zeroed by an opposing force. An object with zero acceleration will have zero net force. Video 2018-04-18, 10 18 57 PM-1ab4yap In this video we see a blue ball rolling across a table. We want to find the unbalanced force that is acting on the ball. The blue ball’s mass is 8.42 g. or 8.42 x 10^-3 kg. By multiplying the ball’s mass by the acceleration of gravity (9.81 m/s^2) we can get the force of gravity of 0.08 N. Since the ball is on the table we can also assume that the normal force acting against gravity is 0.08 N. The ball was moving at approximately a speed of 0.22 m (v) over a course of 1 second (t). Meaning the average acceleration would be 0.22 m/s^2. Force equals ma = F therefore F = 0.002 N.
Newton’s Third Law of Motion: Newton’s third law states that for every action there is an equal and opposite reaction. This means that if a force is applied to an object, an object applying the force will have the same force applied to it. Video 2018-04-18, 11 52 43 PM-1ylk7yt In this video, a bouncy ball falls and hits a table, instead of stopping completely, the ball bounces back up. The same force of gravity that acted on the ball was also the force that caused the ball to move away from the table. In some cases, the object wouldn’t bounce, since I used a bouncy ball for this video, the force caused the ball to bounce back up, other objects like a box or brick would still receive an equal force but it wouldn’t bounce (and might break the table). Combining the Second and Third laws allows us to find out why when a bullet is fired from a gun it can be extremely destructive to any targets but not harm its user. Since the gun has more mass, the force that launches the bullet is the same on the gun but doesn’t move the gun as far due to the gun’s inertia.