Chapter 11.1, Problem 11SSC

(a)

To determine

To draw: A bar graph that describes the forms of energy present in the system where the toy is pushed down thereby compressing the spring.

Explanation of Solution

Initially the dart has gravitational potential energy PE . When it is pushed into the gun barrel, compressing the spring, this gravitational potential energy is converted into elastic potential energy EPE .

Take the ground as the reference level.

  

(b)

To determine

To draw: A bar graph that describes the forms of energy present in the system where the spring expands and the toy jumps.

Explanation of Solution

When the spring expands and the dart leaves the gun, the elastic potential energy stored in the spring is converted to kinetic energy.

Take the ground as the reference level.

  

(c)

To determine

To draw: A bar graph that describes the forms of energy present in the system where the toy reaches the top of its flight.

Explanation of Solution

As the dart goes up, its kinetic energy decreases. When it reaches the maximum height, its velocity becomes 0. At this point, all the kinetic energy is converted to gravitational potential energy. Assume, $h$ is the maximum height it can reach.

Take the ground as the reference level.