Turning Forces Quiz

What is the unit of a moment?

• Joules

• Newton metres

• Watts

What do you call the point about which a force turns?

• Centre of mass

• Pivot

• Balance point

How do you calculate a moment?

• Moment = weight ÷ distance

• Moment = force × perpendicular distance from the pivot

• Moment = mass × gravity

Which of the following statements best describes the law of moments?

• All forces acting on an object must be equal.

• The clockwise moment must be greater than the anticlockwise moment.

• In equilibrium, clockwise moments equal anticlockwise moments.

A see-saw with a 1000 N child 0.5 m from the pivot balances a 500 N child on the other side. How far is the 500 N child from the pivot?

• 0.25 m

• 1 m

• 2 m

What happens if the centre of gravity of an object is not above the pivot?

• The object will spin continuously.

• There is no turning force.

• A turning force is created.

Which of these correctly defines the centre of gravity?

• The point where the object is heaviest.

• The point where all the weight of an object appears to act.

• The middle of the object.

A girl applies a force of 5 N to a door 0.75 m from the hinge. What is the moment?

• 3.75 Nm

• 6.75 Nm

• 0.75 Nm

In which situation is there no turning force on a chair?

• When the centre of gravity is directly above the pivot.

• When the person leans forward.

• When the pivot is at the back legs of the chair.

Why might a tightrope walker use a long pole to help balance?

• It increases their mass.

• It reduces the distance from the pivot.

• It helps distribute weight and stabilise the centre of gravity.