1.5.4 Centre of mass & 1.5.3 Turning effect

Diagram shows 4 objects on a flat surface.

M is the centre of mass of the objects.

Which object is about to fall over?

• A

• B

• C

• D

• 
• 
• 
• 

Passengers are not allowed to stand on the upper deck of double-decker buses.

Why is this?

• They would cause the bus to slow down.

• They would increase the kinetic energy of the bus.

• They would cause the bus to become unstable.

• They would lower the centre of mass of the bus.

Diagram shows a uniform , flat-metal sheet hanging freely from a nail at point A.

A weight also hanging freely on a string tied to A.

Which point is the centre of mass?

• A

• B

• C

• D

The diagram shows a balance being used to find the weight of a baby. The weight of the basket can be ignored.

At equilibrium, the pivot is nearer to the weight W than to the baby.

What is the weight of the baby?

• less than W

• more than W

• W

A beam pivoted at one end has a force of 5.0N acting vertically upwards as shown.

The beam is in equilibrium.

What is the weight of the beam?

• 2.0N

• 3.0 N

• 3.3 N

• 5.0 N

• 
• 
• 
• 

Diagram shows a force being applied to a lever to lift a heavy weight.

Which change would enable the heavy weight to be lifted with smaller force?

• Move the force to the right

• Move the heavy weight to the right

• Move the force to the left

• Move the pivot to the left

Diagram shows a wooden beam with two forces acting on it.

Which way will the beam move?

• accelerate up the page

• accelerate down the page

• turn anticlockwise

• turn clockwise

Diagram shows an object of weight W and an object of weight Z balanced on a uniform metre rule.

Which equation relating to W, Z, a and b is correct?

• W/a = Z/b

• W × Z = a × b

• W × a = Z × b

• W × (a + b) = Z