Projectile motion

Question 1

What is projectile motion?

Answer 1

Movement of a body through the air following a curved flight path under gravity force

Question 2

What factors affect horizontal distance travelled by a projectile and how?

Answer 2

Speed of release = greater speed of release increased distance travelled

Angle of release = 45 degrees is optimal

Height of release = increased height of release increases distance travelled

Aerodynamic factors = Bernoulli and magnus

Question 3

Describe a parabolic flight path and give an example?

Answer 3

• uniform curve symmetrical about it’s highest point
• weight is the dominant force

e.g shot put

Question 4

Describe a non parabolic flight path and give an example?

Answer 4

• asymmetrical flight path about highest point
• air resistance is dominant force

e.g badminton shuttle

Question 5

What is resultant force?

Answer 5

Sum of all forces acting on a body (net force)

Question 6

Describe an aerofoil shape?

Answer 6

Streamlined shape with a curved upper surface and flat lower surface designed to give a body additional lift

Question 7

Describe how an aerofoil shape creates upwards lift?

Answer 7

• curved upper surface forces air to travel further at a higher velocity and lower pressure
• flat lower surface means air travels a shorter distance at a lower velocity and higher pressure
• air moves from a high pressure to a low pressure
• creates upwards lift

Question 8

Describe how downward lift is created?

Answer 8

• inverted aerofoil shape
• air forced to travel further at a higher velocity and lower pressure on curved bottom surface
• air travels shorter distance at lower velocity and higher pressure on flat upper surface
• air moves from a high to low pressure
• created downwards lift

Question 9

How are the different types of spin created?

Answer 9

Topspin = eccentric force applied above COM
Backspin = eccentric force applied below COM
Sidespin (hook) = eccentric force applied to right of COM
Sidespin (slice) = eccentric force applied to left of COM

Question 10

What s magnus force?

Answer 10

Force created from a pressure gradient on opposing surfaces of spinning body moving through air

Question 11

Describe what happens in a hook shot?

Answer 11

• eccentric force applied to right of COM
• air flow opposes motion
• ball rotates to the left
• on the left side air moves at a high velocity and low pressure
• on the right side air moves at a low velocity and high pressure
• pressured gradient formes
• magnus force deviates flight path to the left

Question 12

Describe what happens in a slice shot?

Answer 12

• eccentric force applied to left of COM
• air flow opposes motion
• ball rotates to the right
• on the right side air moves at a high velocity and low pressure
• on the left side air moves at a low velocity and high pressure
• pressured gradient formes
• magnus force deviates flight path to the right