Physics Quiz

What is the correct equation for speed?

• Speed = time ÷ distance

• Speed = distance × time

• Speed = distance ÷ time

• Speed = time ÷ force

Answer explanation

The correct equation for speed is Speed = distance ÷ time. This formula shows that speed is calculated by dividing the distance traveled by the time taken to travel that distance.

The train travels between Station A and Station B. Based on the distance-time graph, what is the total distance covered?

• 100 km

• 150 km

• 200 km

• 250 km

Answer explanation

The distance-time graph shows that the train covers a total distance of 200 km between Station A and Station B, making 200 km the correct answer.

How long does the train take to travel from Station A to Station B?

• 3 hours

• 4 hours

• 5 hours

• 6 hours

Answer explanation

The train takes 5 hours to travel from Station A to Station B, which is the correct answer among the options provided.

Which of the following require unbalanced forces? (Select two answers.)

• A car getting slower in a straight line.

• A bicycle moving at constant speed in a straight line.

• A computer sitting on a desk and not moving.

• A train travelling around a circular track at constant speed.

Answer explanation

Unbalanced forces are required for changes in motion. A car slowing down indicates a force acting against its motion. A train on a circular track experiences centripetal force, also indicating unbalanced forces. The other options involve balanced forces.

A force of 15N is applied to a door handle 0.8m away from the hinge. What is the moment created?

• 10 N·m

• 12 N·m

• 15 N·m

• 20 N·m

Answer explanation

The moment (torque) is calculated using the formula: Moment = Force x Distance. Here, Moment = 15N x 0.8m = 12 N·m. Therefore, the correct answer is 12 N·m.

What is the correct equation for pressure?

• Pressure = force ÷ area

• Pressure = area ÷ force

• Pressure = force × area

• Pressure = force ÷ time

Answer explanation

The correct equation for pressure is Pressure = force ÷ area. This means that pressure is defined as the amount of force applied per unit area, making this choice the accurate representation of the concept.

Why is the pressure inside a bicycle tyre higher than outside?

• There are fewer air molecules inside, increasing pressure.

• Air molecules move more slowly inside the tyre.

• The air molecules inside collide with the walls of the tyre more frequently.

• The tyre absorbs air pressure from the ground.

Answer explanation

The pressure inside a bicycle tyre is higher because the air molecules collide with the tyre walls more frequently. This increased collision rate results in higher pressure compared to the outside air.

Why does the smell of hot soup spread faster?

• The soup releases a special gas when heated.

• The gas particles slow down and take up more space.

• The gas particles move faster and spread more quickly.

• The soup absorbs smells from the environment.

Answer explanation

The correct answer is that gas particles move faster and spread more quickly when heated. This increased movement allows the smell of hot soup to disperse rapidly through the air, making it more noticeable.