Pressure
What is the SI unit of pressure?
Pascal
A metal block has a mass of 720 g and a density of 6 g/cm³. What is its volume?
120 cm3
A ball is floating at rest on the surface of water. Which two forces should be shown on its free-body diagram?
Weight and buoyant force
An object has a density of 0.8 g/cm³ and is placed in water. Water has a density of 1.0 g/cm³.
It will float
A diver moves from a depth of 5 m to 15 m underwater. What happens to the pressure exerted by the water?
It increases
A rectangular metal block has a mass of 1,080 g. Its length is 10 cm and its width is 6 cm. The block has a density of 3 g/cm³. What must be the height of the block?
6 cm
A block is floating at rest. Its weight is 80 N. What must be the buoyant force?
80 N
An object displaces 2 kg of water when completely submerged. Take g=10 m/s2.
What is the buoyant force?
20 N
Two students have the same weight. Student A stands on both feet, while Student B stands on one foot. Which student exerts greater pressure?
B
A student places two objects in water.
Which object will float, and which will sink? Explain your reasoning.
A floats, B neutral / floats
A submerged object has:
What will happen to the object?
30 N it will accelerate upward, it will float
An object has a weight of 150 N. The buoyant force acting on it is 100 N.
50 N downward
A person wearing high-heeled shoes exerts more pressure on the ground than a person wearing flat shoes because the high heels:
Have a smaller contact area
A block has a volume of 150 cm³ and a density of 2.5 g/cm³. What is its mass?
375 grams
A block is resting on a horizontal table. The block has a weight of 100 N. Draw a free-body diagram.
100 N upward (FN) ; 100 N downward (Fg)
A student travels from sea level to the top of a high mountain. What happens to atmospheric pressure?
decreases
Why does pressure in a liquid increase as depth increases?
There is more liquid/particles of fluid above the object.
A large ship is made mostly of steel, which is much denser than water. Yet the ship can float. Why?
Because the ship's hollow structure gives it a large volume compared with its mass
Two blocks have the same weight of 200 N, but they have different contact areas.
Which block produces greater pressure on the ground?
block A
Why is atmospheric pressure generally lower at the top of a mountain than at sea level?
There are fewer air molecules above the person at higher altitude.