P3 - Falling safely

Question 1

When is terminal speed reached?

Answer 1

When the forces are balanced.

Question 2

How is friction reduced?

Answer 2

• lubricating moving parts of machines
• streamlining cars
• shaping car roof boxes
• closing car windows when driving

Question 3

What does less energy waste mean for a car?

Answer 3

• fuel consumption is improved

- the cars top speed is increased

Question 4

What does the size of air resistance force on a falling object depend on?

Answer 4

• its cross sectional area

- its speed

Question 5

What is gravitational field strength measured in?

Answer 5

Newtons per kilogram (N/kg)