Grade 9 Pressure

Which one is correct to describe pressure?

• force per unit area

• area per unit force

• product of area and force

• work done per unit time

Which is NOT the unit of pressure?

• mmHg

• pascal

Which statemen is correct about pressure, force and area?

• Pressure is inversely proportional to area

• Pressure is directly proportional to area

• Pressure is inversely proportional to force

Why is it hard to cut using a dull knife?

• A dull knife has larger contact area than the sharp one, so its pressure is greater.

• A dull knife has smaller contact area than the sharp one, so its pressure is greater.

• A sharp knife has larger contact area than the sharp one, so its pressure is greater.

• A dull knife has larger contact area than the sharp one, so its pressure is smaller.

A force of 500 N is given to 0.02 m². What is the pressure?

• 25 Pa

• 25 kPa

• 10 Pa

• 0.04 kPa

A box has a mass of 5 kg. What is the contact are between the box and the floor to produce pressure of 20 Pa?

Which hole will produce strongest flow of water? Why?

• Hole 1, since the deeper the liquid the greater the pressure

• Hole 3, since the deeper the liquid the greater the pressure

• Hole 1, since the shallower the liquid the greater the pressure

• Hole 3, since the deeper the liquid the smaller the pressure

Which quantity doesn't affect the pressure of liquid?

• density of object

• density of liquid

• gravitational field strength

• depth of liquid

Which length is used to measure the pressure of liquid get by the fish?

• A

• B

• C

• D

Liquid X has smaller density than liquid Y. Which tube has the smallest pressure by the liquid?

• A

• B

• C

• D