21. How does pressure affect the speed of sound in a gas?
a) Higher pressure increases the speed of sound
b) Higher pressure decreases the speed of sound
c) Pressure has no effect on the speed of sound
d) It depends on the density of the gas
22. What is the pressure inside a container if a force of 50 N is applied to an area of 0.1 m²?
a) 500 Pa
b) 5 Pa
c) 5000 Pa
d) 50 Pa
23. Which of the following is an example of pressure in fluids?
a) Water flowing through a pipe
b) A solid block on a table
c) A falling apple
d) A floating balloon
24. How does pressure affect the boiling point of water?
a) Higher pressure increases the boiling point of water
b) Higher pressure decreases the boiling point of water
c) Pressure has no effect on the boiling point of water
d) It depends on the altitude
25. What is the pressure exerted by a force of 200 N on an area of 4 m²?
a) 50 Pa
b) 400 Pa
c) 800 Pa
d) 1000 Pa
