Physics GCSE Pressure in fluids AQA

What is the unit of pressure?

• Newton

• Joule

• Pascal

• Watt

What happens to the pressure in a liquid as the depth increases?

• It decreases

• It remains the same

• It increases

• It fluctuates

What is the formula for calculating pressure in a column of water?

• p = h * ρ * g

• p = m * a

• p = F/A

• p = v/t

What causes atmospheric pressure to decrease with increasing altitude? (choose the BEST answer)

• Decrease in air molecule collisions

• Decrease in the weight of air above the surface

• Decrease in temperature

• Increase in humidity

Answer explanation

In this type of question about the atmosphere, the examiner is looking for you to consider give context, rather than the more general response about collisions (which is also true).

What is the key reason behind why an object floats or sinks in water?

• The object's density compared to water

• The object's color and shape

• The object's mass compared to water

• The salinity of the water

What is a fluid?

• A substance that can flow (liquid or gas)

• It's an alternative name for a liquid

• A liquid with a solid dissolved in it

• It's an alternative name for a gas

What is the unit of pressure that is equal to one newton per square metre?

• Pascal (Pa)

• Joule (J)

• Watt (W)

• Newton (N)

Why does the pressure in a liquid increase with depth?

• Pressure at any point in a liquid is due to the weight of the liquid above that point

• Temperature increases with depth meaning the particles collide with the surface more often

• Pressure is independent of depth

• The mass of the liquid above that point causes pressure to increase

Why does the pressure in a liquid depend on the density of the liquid?

• Pressure is due to the weight of the liquid, and the weight of a liquid depends on its density

• Pressure is independent of density so only depends upon temperature

• Pressure depends only on the height of the liquid

• Pressure is the same for all liquids regardless of density

What is upthrust?

• The resultant force due to the difference in pressure between the top and bottom surfaces of an object submerged in a fluid

• The force on a rocket from its engines causing it to accelerate upwards

• The contact force upwards on any object resting on a horizontal surface

• The resistance of water