Question
The diagram shows a box of dimensions 6.0 cm 8.0 cm 4.0 cm.
The box rests on a flat horizontal surface.
On which face must the box rest in order to exert the least pressure?
face X
face Y
face Z
The pressure is the same for all the faces.
Answer/Explanation
Ans: A
Question
Air in a sealed syringe is slowly compressed by moving the piston. The temperature of the air stays the same.
Which statement about the air is correct?
The pressure of the air decreases because its molecules now travel more slowly.
The pressure of the air decreases because the area of the syringe walls is now smaller.
The pressure of the air increases because its molecules now hit the syringe walls more frequently.
The pressure of the air increases because its molecules now travel more quickly.
Answer/Explanation
Ans: C
Question
A book has a mass of 400 g. The surface of the book in contact with a table has dimensions 0.10 m 0.20 m. The gravitational field strength g is 10 N / kg.
What is the pressure exerted on the table due to the book?
A $0.08 \mathrm{~N} / \mathrm{m}^2$
B $8.0 \mathrm{~N} / m^2$
C $20 \mathrm{~N} / m^2$
D $200 \mathrm{~N} / m^2$
Answer/Explanation
Ans: D
Question
A mercury barometer is used to measure atmospheric pressure.
Which distance gives a measure of the atmospheric pressure?
Answer/Explanation
Ans: B
Question
Air trapped in a sealed bottle increases in temperature.
Which row shows the changes that occur to the trapped air?
| pressure of the air | average speed of molecules in the air |
A | decreases | decreases |
B | decreases | increases |
C | increases | decreases |
D | increases | increases |
Answer/Explanation
Ans: D