Forces in Fluids

An object weighing 30 N displaces a volume of water with a weight 20 N. What will the object do?

• It will sink

• It will float

• It will fly

• None of these answers

A helium-filled balloon will float in air because…

• There is more air than helium

• Helium is less dense than air

• Helium is as dense as air

• Helium is more dense than air

The amount of force pushing on an area is the definition of....

• Fluid
• Viscosity
• Barometer
• Pressure

Which of the statements is true?

• The bottom of the boot exerts more pressure than the shoe as a result of an increase in surface area.
• The bottom of the shoe exerts more pressure than the boot as a result of an decrease in surface area.
• The bottom of the shoe exerts the same pressure as the bottom of the boot.

What pressure does a 4000N horse exert on the ground if each foot is 10cm²?

• 40 N/cm²
• 100 N/cm²
• 400 N/cm²
• 10 N/cm²

If the horse reared up on 2 legs what effect would it have on the pressure?

• it will exert half the pressure it did before
• it will exert the same pressure it did before
• it will exert twice the pressure it did before
• it will exert four times the pressure it did before

Army tank tracks are useful for travelling through the mud because..

• they decrease the force the vehicle exerts on the ground
• they increase the force the vehicle exerts on the ground
• they decrease the pressure the vehicle exerts on the ground
• they increase the pressure the vehicle exerts on the ground

Which of these animals would probably cause the greatest pressure on the ground?

• A fat cow with big feet
• A fat cow with small feet
•  A calf with big feet
• A calf with small feet

Where would you find the largest pressure?

• At the bottom of the ocean
• At the top of Mt Everest
• Close to ground on the Scotch oval
• In a rockpool on the Great Barrier Reef

What is the difference between particles in a gas and a solid?

• gas particles are closer together
• solid particles move faster than gas particles
• solid particles expand on heating
• gas particles have more kinetic energy than solid particles