9La

1       Why is it easier to cut something with a sharp knife than with a blunt one?

A       The area of the knife edge is large so pressure is greater.

B       The area of the knife edge is small so pressure is greater.

C       The area of the knife edge is large so pressure is smaller.

D       The area of the knife edge is small so pressure is smaller.

 

2       If all these birds are the same weight, which bird has the lowest pressure under its feet?

 

A  crow	B  seagull
C  raven	D  chicken

 

3       Which is not a unit for pressure?

A       pascals

B       newtons per square metre

C       kilograms

D       newtons per square millimetre

 

4       A basketball player weighs 500 N.
The area of one of his trainers is 250 cm².
When he puts all his weight on one foot,
how much pressure does he put on the ground?

A       0.5 N/cm²                      B       2 N/cm²

C       250 N/cm²                     D      125 000 N/cm²

 

9Lb

1       The pressure in liquids and gases is caused by:

A       the particles pressing down.

B       the particles pushing up.

C       the particles moving sideways.

D       the particles moving in all directions and colliding with things.

 

2       Why does a dam at the end of a lake need to be wider at the bottom?

A       Water pressure is greater near the surface of the water.

B       There is more water pressure at the bottom of the lake.

C       To use up more concrete.

D       Water pressure decreases with depth.

 

3       When a gas is compressed:

A       the particles bump into the walls of the container less often.

B       the pressure drops.

C       the particles become more spread out.

D       the pressure increases.

 

4       A hydraulic system:

A       uses air to smooth out bumps.

B       uses air to send a force from one place to another.

C       uses a liquid to send a force from one place to another.

D       uses a solid to send a force from one place to another.

 

9Lc

1       In science, a lever is:

A       a complex machine which keeps the size of force you put in the same.

B       a simple machine which changes the size of force you put in.

C       a simple machine which changes the area of force you put in.

D       someone about to finish school.

 

2       Which are the correct labels for the lever shown below?

 

 

A       X = effort, Y = pivot, Z = load

B       X = pivot, Y = effort, Z = load

C       X = load, Y = pivot, Z = effort

D       X = load, Y = effort, Z = pivot

 

3       How many diagrams show levers in action?

 

 

 

A       1            B       2            C       3            D       4

 

4       Which lever will make it easiest to move the rock?

 

 

9Ld

1       The moment of a force is:

A       its turning effect.

B       how long it takes to work.

C       how far it moves.

D       the distance of a force from a pivot.

 

2       You are opening a can of paint with a screwdriver.
You apply a force of 10 N, 20 cm from the pivot.
What is the moment of the force?

A       2 Nm                             B       20 Nm

C       200 Nm                         D      2000 Nm

 

3       What is a seesaw that is ‘in equilibrium’?

A       a balanced seesaw

B       a seesaw with the same weight on each side

C       a seesaw with both people the same distance from the middle

D       a wooden seesaw

 

4       What is the distance from the pivot of the boy on the seesaw?

 

 

         Boy: 300 N ´ ? m           Girl: 450 N ´ 2 m 

A    1 m         B    2 m      C   3 m      D   4 m