# Lesson Worksheet: The Conservation of Mechanical Energy Science

In this worksheet, we will practice explaining the motion of a pendulum for which mechanical energy is conserved.

Q1:

The diagram shows a pendulum. The pendulum bob swings on a string between the positions shown. The only energy transfers occurring for the pendulum are between the kinetic energy for the pendulum and the gravitational potential energy for the pendulum. At which of the following positions is the gravitational potential energy for the pendulum the least? • A • B • C Q2:

The diagram shows a pendulum. The pendulum bob swings on a string between the positions shown. The only energy transfers occurring for the pendulum are between the kinetic energy of the pendulum and the gravitational potential energy of the pendulum. At which of the following positions is the kinetic energy of the pendulum greatest? • A • B • C Q3:

The only energy transfers possible for an object are between the kinetic energy of the object and the gravitational potential energy of the object.

Complete the following: The mechanical energy of the object is .

• Bconserved

Q4:

The only energy transfers possible for an object are between the kinetic energy of the object and the gravitational potential energy of the object. The kinetic energy of the object increases by 4 J.

Fill in the blanks: The gravitational potential energy of the object by J.

• Aincreases, 2
• Bdecreases, 4
• Cdecreases, 2
• Ddecreases, 1
• Eincreases, 4

Q5:

The diagram shows a pendulum. The pendulum is suspended from the top of a box that contains no air. The pendulum bob swings on a string between the positions shown. The motion of the pendulum does not move the box. There is no heating or cooling of the box by its surroundings. Which of the following correctly describes how the first complete swing of the pendulum compares to the fiftieth complete swing of the pendulum? • AThe pendulum will swing the same distance in the same time on swing one and on swing fifty.
• BThe pendulum will swing the same distance on swing one and on swing fifty, but it will take more time to complete swing fifty.
• CThe pendulum will swing a shorter distance on swing fifty than on swing one, but it will take the same time to complete each swing.

Q6:

A pendulum bob is initially at its greatest height. The pendulum then swings so that the bob returns to its original position. How many times is the bob at a position at which the gravitational potential energy of the pendulum is the greatest?

Q7:

The only energy transfers possible for an object are between the kinetic energy of the object and the gravitational potential energy of the object. The gravitational potential energy of the object increases by 5 joules.

Fill in the blanks: The kinetic energy of the object by joules.

• Bdecreases, 5
• Cincreases, 5

Q8:

A pendulum bob is initially at its greatest height. The pendulum then swings so that the bob returns to its original position. How many times is the bob at the position at which the kinetic energy of the pendulum is the greatest?

Q9:

Fill in the blank: The mechanical energy of a pendulum is conserved. The energy transfers for the pendulum are between its kinetic energy and its gravitational potential energy.

• Amain
• Bonly possible

Q10:

A pendulum bob is initially at its greatest height. The pendulum then swings so that the bob returns to its original position. At how many positions of the bob is the kinetic energy of the pendulum the greatest?