9I Quick Quiz

What are forces X and Y?

• X is air resistance, Y is gravity.
•   X is air resistance, Y is friction.
• X is weight, Y is air resistance.
•  X is friction, Y is air resistance.

Balanced forces:

• make objects speed up.
• make objects slow down.
• do not change the speed of moving objects.
•  only affect stationary objects.

 A boat has a forwards force on it of 500 N and water resistance is 400 N. Which statement is true?

•  The forces are balanced and the boat will go faster.
• The forces are balanced and the boat will continue to move at the same speed.
• The forces are unbalanced and the boat will go faster.
• The forces are unbalanced and the boat will continue to move at the same speed.

All vehicles have a top speed. This is when:

•   the air resistance is the same as the force from the engine
•  the drag and friction forces balance the maximum force from the engine
•  the force from the engine balances friction in the wheels 
•   the drag forces balance the friction forces.

 Which of these is not a way in which energy is stored?

• chemical
• kinetic
• Thermal
• Electrical

Which of these is a way in which energy can be transferred?

• movement
• Light
• petrol
• potential

In which ways is energy most often transferred as wasted energy?

•  heating and light
• heating and sound
•  sound and light
•  sound and kinetic

Which of these machines is the more efficient and why?

• Y because it does not waste as much energy as X.
• Y because it wastes more energy than X.
•  X because it transfers the most energy.
•  X because it wastes more energy than Y.

The speed of a car is a measure of how:

• A  far it is travelling.
• A  fast it is travelling.
• A  long it is travelling.
• A  high it is travelling.

A bus travelled a distance of 20 km in 2 hours. Its speed was:

• 0.1 km/h.
• 40 km/h.
• 20 km/h.
• 10 km/h.