Yr13: 🟠 4.1 Linear Motion: The Relationship Between Impulse & Increasing & Decreasing Momentum in Sprinting

Question 1

Impulse

Answer 1

The time it takes a force to be applied to an object or body and can be calculated by

Impulse (newton seconds) = force x time

Question 2

What does an increase in impulse mean

Answer 2

Result in an increase in the rate of change of momentum, which causes a large change in velocity.

For example, tennis player follows through with a racket to increase the amount of time the racket is in contact with the tennis ball. This increases the outgoing momentum of the balk which causes the ball to travel faster

Question 3

How else can using impulse to increase momentum be achieved

Answer 3

Through the increase of the amount of muscular force that is applied.

Also through increasing the amount of time in which force is applied (e.g hammer through, swinging 3/4 times before throwing)

Question 4

How does impulse decrease momentum ?

Answer 4

Occurs by increasing the time forces act upon them

E.g landing from gymnastics,

Question 5

What is a net impulse

Answer 5

A combination of positive and negative impulses

Question 6

X and y axis of graph showing impulse

Answer 6

X axis = time (s)

Y axis = force (N)

Question 7

Unit of measurements for impulse

Answer 7

N/S

Question 8

2 ways impulse can be increased

Answer 8

1. Increase the force applied
   • Apply a greater force to the object (e.g. hitting a ball harder).
   • This increases the change in momentum.
2. Increase the time over which the force is applied
   • Apply the force for longer (e.g. following through when kicking or throwing).
   • Even with the same force, a longer contact time increases impulse.

Question 9

What is a positive / negative impulse

Answer 9

🔹 Positive impulse

👉 Makes an object go faster (in the same direction)
• Force is applied in the same direction as movement
• Momentum increases

✅ Example:
• Kicking a football forward
• Pushing a moving shopping cart to speed it up

Positive impulse = speeds things up

⸻

🔹 Negative impulse

👉 Makes an object slow down or stop
• Force is applied in the opposite direction to movement
• Momentum decreases

✅ Example:
• Catching a ball
• Braking on a bike
• A goalkeeper stopping a shot