Task 5: Sally Pearson
1. Explain the concept of Newton's First Law of Motion - Inertia:
Newton's first law of motion is often stated as "An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction."
There are two parts to this statement, which are that one predicts the behaviour of stationary objects and the other one predicts the behaviour of moving objects. The behaviour of all objects can be described by saying that objects tend to keep on doing what they are doing (unless acted upon by an unbalanced force). If at rest, they will continue at this same state of rest. If in motion, they will continue in this same state of motion. Basically, the state of motion of an object is maintained as long as the object is not acted upon by an unbalanced force. So, as long as the forces are balanced, the first law of motion applies.
2. Detail the effects of Inertia on the athlete, their sport and the equipment used:
Inertia in relation to my athlete, Sally Pearson is evident in the way in which shorter legs are more suited to sprints as they have a lower point of inertia because short legs are easier to move than long legs. The combination of powerful muscles and a lower point of inertia creates a faster stride rate. The way in which Sally Pearson sprints at the start of a race exerts great muscle power to overcome gravity and body inertia in order to reach maximum velocity. The athlete's job in this situation, is to drive downward and backward against the ground.
The motion of hurdling is an example of a projected object that continues its motion by its own inertia and is influenced only by the downward force of gravity (projectile motion). As the hurdler will jump at a certain launch angle and land at that same angle on the other side of the hurdle. The smaller the angle take off, the less time it will take to pass over the hurdle and the lower the centre of gravity will be, but also with a smaller angle comes a greater distance covered. This motion also means that hurdlers will reach maximum height before clearing the hurdle.
Newton's first law of motion is often stated as "An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction."
There are two parts to this statement, which are that one predicts the behaviour of stationary objects and the other one predicts the behaviour of moving objects. The behaviour of all objects can be described by saying that objects tend to keep on doing what they are doing (unless acted upon by an unbalanced force). If at rest, they will continue at this same state of rest. If in motion, they will continue in this same state of motion. Basically, the state of motion of an object is maintained as long as the object is not acted upon by an unbalanced force. So, as long as the forces are balanced, the first law of motion applies.
2. Detail the effects of Inertia on the athlete, their sport and the equipment used:
Inertia in relation to my athlete, Sally Pearson is evident in the way in which shorter legs are more suited to sprints as they have a lower point of inertia because short legs are easier to move than long legs. The combination of powerful muscles and a lower point of inertia creates a faster stride rate. The way in which Sally Pearson sprints at the start of a race exerts great muscle power to overcome gravity and body inertia in order to reach maximum velocity. The athlete's job in this situation, is to drive downward and backward against the ground.
The motion of hurdling is an example of a projected object that continues its motion by its own inertia and is influenced only by the downward force of gravity (projectile motion). As the hurdler will jump at a certain launch angle and land at that same angle on the other side of the hurdle. The smaller the angle take off, the less time it will take to pass over the hurdle and the lower the centre of gravity will be, but also with a smaller angle comes a greater distance covered. This motion also means that hurdlers will reach maximum height before clearing the hurdle.