Projectile Motion

Question 1

What is projectile motion?

Answer 1

Projectile motion- the motion observed when bodies are projected into the air and are under the influence and under the influence of gravity (and air resistance) only- acceleration is constant at –9.81 m/s/s

Projectile- a body undergoing projectile motion; it can be an object, a person, or both.

Question 2

What is gravity and air resistance?

Answer 2

Gravity- the attraction influence that pulls an object to its surface. It uniformly accelerates a projectile towards the earth’s surface at –9.81 m/s/s.

Air resistance- limits the motion of a particle. Compared to gravity, it’s often minimal/negligible, so it is often neglected.

Question 3

What are the key features of projectile motion?

Answer 3

Trajectory- flight path of a projectile through the air

Parabola- trajectory follows a ‘parabolic’ curved shape that’s symmetrical about its apex

Apex- highest point reached by a projectile

Range- horizontal displacement of projectile

Question 4

What is projection angle?

Answer 4

The angle at release determines the shape of the trajectory, all other factors being equal

A positive angle is >= 0, 0 degrees = horizontal trajectory, 90 degrees = vertical trajectory (follows a straight up and down line), a negative angle is < 0 (not considered projectile motion)

0-90 degrees = oblique trajectory, parabolic shape, symmetrical about the apex

Projection angle influences the relative magnitude of vertical and horizontal velocity components

If no projection height, there’s no flight

At 45-degree projection angle, horizontal and vertical components are equal

0-45 degrees have greater horizontal component than vertical component

Question 5

What is projection velocity?

Answer 5

Projection velocity determines the height and range of a projectile, all other factors being equal

Vertical velocity determines height and time of flight

Horizontal velocity determines range

Question 6

What is projection height?

Answer 6

Projection height is the relative difference in height between release and landing; it’s the vertical displacement between the point of release and landing

Projection height = 0, height at release is the same as landing; symmetrical, parabolic trajectory

Not all projectiles land at the same height they were released from

Projection height > 0, height at release is above landing

Projection height < 0, height at release is below landing

Projection height not equal to zero is still parabolic, just not symmetrical

Maximum range is produced with a release angle of 45 degrees when projection height = 0

Question 7

What categories can the goals of projectile motion be considered to fall within?

Answer 7

Predicting trajectory (catching/receiving an object, batting/striking an object)

Controlling trajectory (tennis serve, somersaulting, passing/shooting an object)

Maximising/optimising aspects of trajectory (high/long/triple jump, throwing events for distance)