# Pressure and moments quiz

#### Quiz Description

In this quiz, we will be focusing on a combination of Pressure and moment. In Physics, students are usually tested from this particular topic, so recommendations are that taking our quizzes will train you well in preparation for these exams and tests. This particular quiz will be talking more about the application of moments and pressure. For example, riding a bicycle is an application of moments, but there is also force, and hence pressure application as well.

Now, pressure can simply be defined as Force per unit area acting on an object.
Mathematically, P=F/A
This definition is valid only for solid objects. For fluids, the pressure is defined in terms of density, gravity, and the depth of the fluid. It is said to be the compressive stress at some point within a fluid. Mathematically stated as
P=Density x Gravity x Fluid depth

The moment of a force is the turning effect of that force. These turning effects usually act either in the clockwise or the anticlockwise direction about a point known as the fulcrum or pivot. In other words, a moment can be defined as the product of force and the distance of the force from the pivot of a rotating object.

After taking our quizzes,you will understand that in the case of a bicycle in motion as earlier said, there is a force from your feets or as we can call it pressure since it is acting through an area on the pedal, this force now causes rotation in a particular direction and this is the moment. If you want to see more applications and even find out about some yourself, do take the quiz.
Good luck!

Which statement is NOT true ?

Correct
• the base of a dam is wider at the bottom than the top because that is where the greatest pressure is
•  the pressure in water acts in all directions
•  the deeper a diver goes to examine the dam wall, the more nitrogen from the air supply dissolves in the blood
•  the pressure in water decreases with increase in depth of water

A spanner is a useful tool to apply the turning effect of a force or a moment. Which is a FALSE statement about the situation?

Correct
•  the shorter the spanner, the smaller is the maximum turning force that can be produced
•   the middle of the spanner acts as the 'lever pivot point'
•  applying 'loosening oil' to the bolt and nut reduces friction
•  in tightening or loosening a nut, the spanner must overcome the force of friction

Examples to help you get to the point of the question! or do you get a sinking feeling because P = F / A! Which features is designed to reduce the pressure of the situation?

Correct
• the blades of ice skates
•  the crampons on a mountain climbers boots
•  a roofer laying a ladder across a roof to work on a repair

A bag of sugar has a base of 6 cm x 10 cm. If it weighs 18 N, what pressure does it create standing on a shelf?

Correct
•   1.8 N/cm2
•  0.3 N/cm2
• 3 N/cm2
•  18 N/cm2

Which statement is FALSE about being trodden on by a stiletto heeled shoe?

Correct
•   the smaller the under surface of the stiletto heal, the higher the pressure created
•  it is less painful if trodden on by the front part of the shoe, rather than the stiletto heel, because the weight of the person is spread over a smaller area
•   the stiletto heel produces a high pressure situation
•  the stiletto heel causes a high pressure because a significant weight acts on a small surface area

Which statement is FALSE about being trodden on by a stiletto heeled shoe?

Correct
•   the stiletto heel produces a high pressure situation
•  it is less painful if trodden on by the front part of the shoe, rather than the stiletto heel, because the weight of the person is spread over a larger area
•  the stiletto heel causes a high pressure because a significant weight acts on a small surface area
•  the smaller the under surface of the stiletto heel, the lower the pressure created

The bones and muscles of your skeleton are a mechanical system to do various physical tasks e.g. lifting, walking etc. Which word best matches the phrase the weight of a lifted object x the length of your arm?

Correct
•   a lever
•   a pivot point or fulcrum
•     a force
• a moment

Which word matches the phrase can be readily reduced in volume under pressure?

Correct
• hydraulic
• pneumatic
• compressible
• incompressible

Which statement is FALSE about being trodden on by a stiletto heeled shoe?

Correct
• the stiletto heel causes a high pressure because a small weight acts on a large surface area
•   the stiletto heel produces a high pressure situation
•  the smaller the under surface of the stiletto heel, the higher the pressure created
•   it is less painful if trodden on by the front part of the shoe, rather than the stiletto heel, because the weight of the person is spread over a larger area

Which of the following is a unit of pressure?

Correct
• m2
• N
• Pa
• Nm

A stiletto heal has a base area of 3 cm2. If the woman weighs 750 N, what pressure does she create on the floor when standing on one heel?

Correct
• 2250 N/m2
• 2250 N/cm2
• 250 N/m2
• 250 N/cm2

Which of the following is a unit of a moment?

Correct
• metres squared
•   newtons x metres
•  newtons per square metre
• newtons

Examples to help you get to the point of the question! or do you get a sinking feeling because P = F / A! Which features is designed to increase the pressure of the situation?

Correct
•  the caterpillar tracks of a building site vehicle
• an elephant's foot
• the blades of ice skates
•  the skis for mountain sports

Which statement is FALSE about being trodden on by a stiletto heeled shoe?

Correct
• the stiletto heel causes a high pressure because a significant weight acts on a small surface area
•  the smaller the under surface of the stiletto heel, the higher the pressure created
• the stiletto heel produces a low pressure situation
•  it is less painful if trodden on by the front part of the shoe, rather than the stiletto heel, because the weight of the person is spread over a larger area

Which statement is NOT true about the material inside the cylinders and pipes of a hydraulic jack or car braking system?

Correct
•   although not easily compressed to a smaller volume, solids are no good because they are not fluid
•  if air gets into a hydraulic system, the system becomes less effective because air readily leaks out
•  liquids are good to use because they are fluid and not readily compressed to a smaller volume
•  although very fluid, gases are no good because they are too easily compressed to a smaller volume