Physics 9 - Final Assessment Part 1 (Pressure)

When a diver swims down from the surface of the water to a depth of 10 m, the pressure experienced increases from 100 000 N/m² to 200 000 N/m² . Which statement explains this increase in pressure?

• Water cannot be compressed.

• The density of the water increases with depth.

• The gravitational field strength increases with depth.

• The weight of water above the diver increases with depth.

Tractors have large tyres. These help to prevent the wheels from sinking into soft ground. Which statement explains this?

• Larger tyres exert a greater force on the ground. 

• Larger tyres exert a smaller force on the ground. 

• Larger tyres exert a greater pressure on the ground. 

• Larger tyres exert a smaller pressure on the ground.

Why is it easier to push a sharp nail, rather than a blunt nail, into a piece of wood?

• The sharp nail exerts a larger force on the wood. 

• The sharp nail exerts a smaller force on the wood.

•  

  The sharp nail exerts a larger pressure on the wood. 

  .

• The sharp nail exerts a smaller pressure on the wood

The water in a swimming pool exerts a pressure at the bottom of the pool. Which graph shows the relationship between the pressure exerted by the water and the depth of water in the pool? 

(Assume the density of water is constant.)

• A

• B

• C

• D

An object is a depth h below the surface of a liquid. The pressure due to the liquid at this depth is p.

The gravitational field strength is g. What is the density 𝞺 of the liquid?

• 
• 
• 
• 

A woman has a weight of 600 N. She stands on a horizontal floor. The area of her feet in contact with the floor is 0.050 m². What is the pressure she exerts on the floor?

• A

• B

• C

• D

A rectangular marble block has dimensions 1 m by 1 m by 5 m and weighs 125 000N. The marble block is stored with the long side resting on the ground, as in diagram 1. 

What is the change in the pressure on the ground due to the block when the block is stored as in diagram 2 rather than diagram 1?

•  a decrease of 25000 N/m²

• an increase of 100 000 N/ m²

• an increase of 125 000 N/ m²

• no change

A solid cube has sides 0.50 m long and a mass of 120 kg. It stands on the ground on one face. Which pressure does the cube exert on the ground?

• 480 kg/ m³

• 960 kg/ m³

• 4700 N/ m² 

• 9400N/ m²

A dam holds water in a reservoir. The height of the water in the reservoir is 15 m. 

The density of water is 1000 kg/ m³ . What is the pressure due to the water at the bottom of the dam?

• 6.8 Pa

• 1500 Pa

• 15 000 Pa        

• 150 000 Pa

The density of sea water is 1030 kg /m³ . The gravitational field strength on the Earth is 9.8N/ kg. Atmospheric pressure is 101 000 Pa. At which depth in sea water is the total pressure due to the atmosphere and the water equal to 513 000 Pa?

•  40.8 m

• 50.8 m

• 400 m

• 498 m