Newton's three laws of motion

1. Newton’s first law:

 “An object will remain at rest or continue to move with constant velocity as long as the net force equals zero.” (Blazevich, 2010)

This first law is also referred to Newton’s Law of inertia. This law implies that all objects with a mass have inertia and the larger the mass, the more difficult it is to change the objects state of motion (inertia) (Blazevich, 2010). In order to change the state of motion of an object, we need to apply a force. Newton’s first law applies to the basketball jump shot in relation to how the athletes propel themselves off the ground and into the air as well as the motion of the ball itself.

The aim of a jump shot is for the athlete to get an edge and gain extra elevation over the opponent. In order to achieve such a shot the athlete needs to adjust their movement to a vertical motion.

The ball itself also applies to this first law of motion due to several external forces acting upon the ball (Ville, 2011). If these forces did not exist the ball would continues to fall in the direction it was already travelling. The external forces acting on the ball when playing outside are gravity, air and wind which is known as 'drag' on the ball. Gravity acts as an external force due to the fact it pulls the ball down (Ville, 2011).

Figure 1.1 – The picture above is a visual example of the jump shot being executed. The athlete has propelled himself vertically off the ground in order to extend the shot over the defender.

Newton's second law comes into play when considering the change of the ball and athletes state of motion, e.g. In order to vertically jump higher the equation of 'force equals mass x acceleration' needs to be studied (Blazevich, 2010).

2. Newton’s second law:

“The acceleration of an object is proportional to the net force acting on it and inversely proportional to the mass of the object” (Blazevich, 2010). F=m x a

Force needs to be applied in order to change the state of motion of an object, which then produces acceleration (Blazevich, 2010). Newton’s second law states that “the lighter the object the faster it will accelerate” (Blazevich, 2010). The greater the mass of an object the greater the force needed in order to accelerate the object for example, depending on the mass of the ball the force will need to be adjusted in order for the ball to travel the same distance (using a tennis ball rather than a basket ball to execute a jump shot). Isaac Newton’s created an equation in order to calculate the second law as Force = mass x acceleration (F=m x a).

In basketball athletes constantly use force whether it is passing the ball or when shooting for a goal. When executing a jump shot the athletes act as the force whilst the ball equals the mass and cause acceleration. This means that the athletes need to use a suitable amount of force when shooting the ball because when the incorrect force is applied it will lead the ball to go in another direction as to where the ball was suppose to fall (Ville, 2011) In relation to the jump shot when the ball is released (accelerated) out of the hands, this caused the ball to gain momentum (Dr Simonetti, J., 1994).

The equation of F=m x a also proves that in order to increase acceleration of an object, a bigger force needs to be applied (Blazevich, 2010). Newton's third law needs to be considered as every action has an equal reaction.

3. Newton’s third law:

“For every action, there is an equal and opposite reaction.” (Blazevich, 2010)

Newton’s third law relates closely to Newton’s second law as it relates to the concept of force being applied to any object. Newton's third law is apparent every time there is a force applied, as there is an equal and opposite force applied back. The idea of every action having a reaction is what enables the athlete to propel themselves off the ground into a vertical jump. When the athlete bends their knees in preparation to execute a jump shot, they send force into the ground (Ville, 2011). Both Ville (2011) and Blazevich (2010) acknowledge that due to the ground having greater mass than the athlete the force travels back to the athlete and propels them straight up, which allows them to jump straight up in the air (Ville, 2011).

In terms of applying Newton’s third law of motion when taking a shot for goal, the focus is on the athlete and the ball.  When the ball is placed in the athlete’s hands, the athlete’s hands act as the force, which is applied to the ball. When the force is applied the ball reacts and creating a force against the athlete’s hands.  Because the mass of the athlete is greater than that of the ball, the ball propels itself forward whilst the athlete remains in the same position (Dr Simonetti, J., 1994).

Figure 1.2 – This picture above is a visual demonstration of the equal and opposite direction between the player and the ground. In the first frame the force is applied by the athlete when bending his knees and pushing himself into the ground. Due the greater mass of the ground the force flows straight back into the player, which results in a vertical jump, frame 3.

Figure 1.3 – This picture above is a visual demonstration of the equal and opposite reaction of the ball and the athletes hand. The force applied by the hand is what accelerates the ball upwards. The equal and opposite force is the force that the ball is applying to the athletes hand.