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Questions and Answers
What is the formula for calculating pressure?
What is the formula for calculating pressure?
What effect does increasing the surface area have on pressure, assuming the force remains constant?
What effect does increasing the surface area have on pressure, assuming the force remains constant?
Why does a person hurt themselves while sitting on a drawing pin but not when lying on a bed of nails?
Why does a person hurt themselves while sitting on a drawing pin but not when lying on a bed of nails?
A woman weighing 550 N wears stiletto heels with a surface area of 1 cm². What is the pressure exerted by each heel?
A woman weighing 550 N wears stiletto heels with a surface area of 1 cm². What is the pressure exerted by each heel?
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What characteristic of gas molecules is described in the particle model of gas?
What characteristic of gas molecules is described in the particle model of gas?
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What property of liquids allows hydraulic machines to transmit pressure uniformly throughout?
What property of liquids allows hydraulic machines to transmit pressure uniformly throughout?
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What is the output force produced by the hydraulic jack if the input force is 12N and the input and output areas are 0.01 m² and 0.1 m² respectively?
What is the output force produced by the hydraulic jack if the input force is 12N and the input and output areas are 0.01 m² and 0.1 m² respectively?
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In a hydraulic brake system, when the brake pedal is pressed, what happens to the fluid inside the cylinder?
In a hydraulic brake system, when the brake pedal is pressed, what happens to the fluid inside the cylinder?
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Why is the hydraulic jack referred to as a force multiplier?
Why is the hydraulic jack referred to as a force multiplier?
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In the braking system of a family car, which statement is true regarding the power generated by the braking system?
In the braking system of a family car, which statement is true regarding the power generated by the braking system?
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What happens to liquid pressure as depth increases within a container?
What happens to liquid pressure as depth increases within a container?
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Which statement accurately describes the water jets from holes in a container filled with liquid?
Which statement accurately describes the water jets from holes in a container filled with liquid?
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Why does pressure decrease as one moves upward in a liquid container?
Why does pressure decrease as one moves upward in a liquid container?
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How does liquid pressure in a container act?
How does liquid pressure in a container act?
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What primarily causes the pressure exerted by a liquid in a container?
What primarily causes the pressure exerted by a liquid in a container?
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How does the density of a liquid influence the pressure it exerts?
How does the density of a liquid influence the pressure it exerts?
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What is the primary reason that pressure in a liquid does not depend on the shape of the container?
What is the primary reason that pressure in a liquid does not depend on the shape of the container?
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Which of the following statements about hydrostatic pressure is true?
Which of the following statements about hydrostatic pressure is true?
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What pressure does a tank's base experience when it holds water weighing 4500 N and has a base area of 1.5 m²?
What pressure does a tank's base experience when it holds water weighing 4500 N and has a base area of 1.5 m²?
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Why do submarines require strong, thick walls?
Why do submarines require strong, thick walls?
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What is atmospheric pressure primarily caused by?
What is atmospheric pressure primarily caused by?
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What happens to the pressure of a gas when its volume is decreased?
What happens to the pressure of a gas when its volume is decreased?
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Why are we not crushed by atmospheric pressure?
Why are we not crushed by atmospheric pressure?
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What must occur to maintain a constant temperature while compressing a gas?
What must occur to maintain a constant temperature while compressing a gas?
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Which of the following is an example of atmospheric pressure being used in a practical scenario?
Which of the following is an example of atmospheric pressure being used in a practical scenario?
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What occurs inside a fully inflated balloon compared to the outside?
What occurs inside a fully inflated balloon compared to the outside?
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In the experiment with the piston and gas, what is indicated by the term 'steady temperature'?
In the experiment with the piston and gas, what is indicated by the term 'steady temperature'?
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What causes the balloons' material to exert an inward force when inflated?
What causes the balloons' material to exert an inward force when inflated?
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What is the primary reason a boat can float on water?
What is the primary reason a boat can float on water?
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How is density calculated?
How is density calculated?
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Why do objects with a density less than that of water float?
Why do objects with a density less than that of water float?
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What happens to pressure as you reduce the surface area of an object while applying the same force?
What happens to pressure as you reduce the surface area of an object while applying the same force?
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What effect does the high salt content in the Dead Sea have on floating?
What effect does the high salt content in the Dead Sea have on floating?
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What happens when a person lies on thousands of nails?
What happens when a person lies on thousands of nails?
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How does the pressure created by ice skates affect the ice below?
How does the pressure created by ice skates affect the ice below?
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What is a consequence of wearing stiletto heels?
What is a consequence of wearing stiletto heels?
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What role do studs on football or hockey boots play?
What role do studs on football or hockey boots play?
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What occurs when the forces acting on a stationary object are unbalanced?
What occurs when the forces acting on a stationary object are unbalanced?
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If a box weighs 50N and experiences 20N of air resistance, what is the resultant unbalanced force acting on it?
If a box weighs 50N and experiences 20N of air resistance, what is the resultant unbalanced force acting on it?
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In a Tug-of-War scenario where one team pulls with a force of 400N and the other with 300N, in which direction will the rope move?
In a Tug-of-War scenario where one team pulls with a force of 400N and the other with 300N, in which direction will the rope move?
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What happens to a moving object when the forces acting on it become unbalanced?
What happens to a moving object when the forces acting on it become unbalanced?
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Which statement accurately describes a resultant force of 100N in a Tug-of-War scenario?
Which statement accurately describes a resultant force of 100N in a Tug-of-War scenario?
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What happens to the motion of a car if the forward force is equal to the force of air resistance?
What happens to the motion of a car if the forward force is equal to the force of air resistance?
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What is the resultant force if a 1000 N force is acting to the right and a 3800 N force is acting to the left?
What is the resultant force if a 1000 N force is acting to the right and a 3800 N force is acting to the left?
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Which of the following statements about upthrust is true?
Which of the following statements about upthrust is true?
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What are the effects of unbalanced forces on an object?
What are the effects of unbalanced forces on an object?
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According to Archimedes' principle, when an object is submerged in water, what causes it to appear lighter?
According to Archimedes' principle, when an object is submerged in water, what causes it to appear lighter?
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What happens to an object when balanced forces are acting on it?
What happens to an object when balanced forces are acting on it?
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In the example of a skydiver falling at a steady speed, which forces are acting on him?
In the example of a skydiver falling at a steady speed, which forces are acting on him?
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What is the combined effect of unbalanced forces called?
What is the combined effect of unbalanced forces called?
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According to Newton's First Law of Motion, what will happen to an object with no external force acting on it?
According to Newton's First Law of Motion, what will happen to an object with no external force acting on it?
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If a box weighs 50 N and experiences an air resistance of 20 N, what is the resultant force acting on it?
If a box weighs 50 N and experiences an air resistance of 20 N, what is the resultant force acting on it?
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Study Notes
Atmospheric Pressure
- Air has weight and presses on everything it touches
- Atmospheric pressure or air pressure is the force exerted on the surface of the Earth by the gravitational attraction of the Earth on the air above it
- At sea level, atmospheric pressure is about 100 kilopascals (kPa)
- This is equivalent to the weight of ten cars pressing on every square metre
- Surprisingly, people aren't crushed because the pressure in the lungs and blood systems exactly matches the pressure of the air around them
Pressure and Volume
- If a gas is squashed into a smaller volume, its pressure rises
- The diagram shows an experiment to find out more about the link between pressure and volume
- Some gas (air) is trapped in a cylinder. The gas is compressed by pushing the piston into the cylinder
- The pressure and volume are measured at different stages
- Compressing the gas heats it up, causing its molecules to move faster
- This also increases the pressure
- Compression must therefore be carried out very slowly so that the gas can lose heat and keep a steady temperature
Pressure in Liquids
- When a liquid is poured into a container, the weight of the liquid pushes down on the base, creating a pressure
- Pressure and depth are not the same at all depths
- Pressure is high at the bottom of the container but gradually decreases as you get nearer the top
- This can be shown by drilling small holes in the container and filling it with water. The diagram shows jets of water coming from the holes.
- Notice that the top jet does not travel as far as the jets from the holes below because the pressure is not so large
- Notice that the direction of the pressure causing the jets of water is outwards—pressure in a liquid acts in equally all directions
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Description
Test your knowledge on the principles of pressure, hydraulic systems, and the behavior of gases. This quiz covers key concepts such as pressure calculations, the effects of surface area, and hydraulic machines' functionality. Answer questions related to real-life applications, like stiletto heels and hydraulic jacks.
