P

A car is designed to be stable. To achieve good stability, where is the centre of mass of the car?

• above the front wheels

• above the rear wheels

• as high in the car as possible

• as low in the car as possible

A beam pivoted at one end has a force of 5.0N acting vertically upwards on it as shown. The beam is in equilibrium.

What is the weight of the beam?

• 2 N

• 3 N

• 3.3 N

• 5 N

The diagram shows four shapes, cut from the same piece of card. Which shape has its centre of mass nearest to the base line?

• A

• B

• C

• D

The diagram shows a wheelbarrow and its load, which have a total weight of 150N. This is supported by a vertical force F at the ends of the handles. What is the value of F?

• 75 N
  

• 150 N
  

• 225 N
  

• 300 N
  

A man uses clay to make a pot. He wants the pot to be as stable as possible when placed on a flat surface. Which two features of the pot must the man consider?

• the area of the base and the height of the centre of gravity

• the density of the clay and the area of the base

• the density of the clay and the height of the centre of gravity

• the weight and the height of the centre of gravity

Which part of the graph shows the limit of proportionality for an elastic solid?

• O

• OP

• P

• PQ

An extension-load graph for a wire is shown. What is the load at the limit of proportionality for the wire?

• 4 N

• 15 N

• 60 N

• 70 N

A steel spring is stretched by a load. The load is increased. At first the extension is proportional to the load. The spring reaches its limit of proportionality at L. Which is the correct graph of the extension against load for the spring?

• A

• B

• C

• D

A spring extends by 4cm when 10N is suspended from it. Two of these springs are used as shown to carry a 30N load. What is the extension of each spring?

• 4 cm

• 6 cm

• 8 cm

• 12 cm

Which property of a body can not be changed if a force is applied to it?

• its mass

• its shape

• its size

• its velocity