MOMENTS AND CENTRE OF GRAVITY

• A

• B

• C

• D

• A

• B

• C

• D

The diagram shows an L-shaped piece of card suspended freely from a pin at B.

When the card is pushed, it swings and then comes to a stop in the position shown.

At which labelled point is the centre of mass of the card?

• A

• B

• C

• D

Two more identical bags of rice are added to the other five. The average position of the bags on

the beam does not change.

What mass now balances the bags?

• 3.5 kg

• 7.0 kg

• 12 kg

• 14 kg

• moving X to the left

• moving X to the right

• moving Y to the right

• moving the pivot to the left

• less than 40 N

• 40 N

• more than 40 N

• impossible to tell without a scale on the beam

The diagram shows four objects on a flat surface.

The centre of mass of each object is marked M.

Which object is about to fall over?

• A

• B

• C

• D

The diagram shows a uniform beam being used as a balance. The beam is pivoted at its centre.

A 1.0 N weight is attached to one end of the beam. An empty pan weighing 0.2 N is attached to

the other end of the beam.

• 5

• 8

• 10

• 12

• All the forces are equal in size.

• The resultant force on the beam is in the opposite direction to the resultant turning effect.

• The resultant force on the beam is zero and the resultant turning effect on the beam is zero.

• The total upward force is twice the total downward force.

The diagrams show four solid cones. The centre of mass of each cone is marked by a point

labelled M.

Which cone is the most stable?

• A

• B

• C

• D