26. Which of the following is an example of a second-class lever?
a) A seesaw
b) A wheelbarrow
c) Pliers
d) A hammer
27. Which of the following is an example of a third-class lever?
a) A seesaw
b) A wheelbarrow
c) Pliers
d) A hammer
28. Which of the following statements is true about potential energy?
a) It is the energy of motion
b) It is the energy of position or state
c) It is always positive
d) It is always negative
29. Which of the following statements is true about kinetic energy?
a) It is the energy of motion
b) It is the energy of position or state
c) It is always positive
d) It is always negative
30. Which of the following statements is true about the law of conservation of energy?
a) Energy can be created or destroyed
b) Energy can only be converted from one form to another
c) The total energy of a system always increases
d) The total energy of a system always decreases
