PROJECTILE MOTION Flashcards
Projectile motion
A projectile motion is an object that is launched, hurled or thrown (from a gun or tennis ball hit by a racquet)
- The path of a projectile is called a trajectory
- A human body can also be projectile (diver)
- A projectile is any airborne object and includes sporting equipment such as balls, shots, javelins and discuses as well as people (e.g. a long jumper, high jumper or diver).
Factors affecting the path of projectile
Gravity affects a projectile vertically by forcing it to the ground. If there was no gravity on Earth, a javelin or shot-put might continue through the air forever, and a volleyballer who launches into the air to block a ball would continue upwards until they hit the roof.
vertical component
influenced by gravity, specifically to the height reached by the projectile (no gravity means projectile will keep going
Example: completing successful high jump
horizontal component
is affected by air resistance and relate to the horizontal distance covered by the projectile
- Air resistance is very impotent
- Maximising horizontal component of boys motion would resulting a longer long jump
The main factors of projectile motion that athletes can control and manipulate are the:
- speed of release
- angle of release
- height of release.
speed of release
The force applied to the projectile will have a large impact on its motion. The force can vary in amount as well as in the direction of application. The greater the force applied to the projectile, the greater the speed and the further it will travel, all other factors being equal.
- A technique to increase force is to use as many body parts as possible (as discussed in the section on force summation).
angle of release
In sport, where maximal horizontal distance of a projectile is desired, there is an optimal angle of release, to minimise the effects of both gravity and air resistance.
- for example, a shot putter, has an optimal angle of release of just below 45 degrees because they are releasing the shot from the shoulder, which is approximately 1.5 meters (depending on the height of the athlete) above the landing point of the ground.
height of release
If the angle and speed of release are constant, an object released from a higher point will travel further than one released from a lower point
- A taller athlete who naturally releases a ball when throwing would therefore have an advantage over a shorter athlete.
