Unit 5 Sumative Quiz - Science G10M

A system with a spring and a suspended mass is set into oscillation in a lab experiment. After a few minutes, the oscillations become smaller until they stop. What conclusions can be drawn from this situation?

• The total mechanical energy of the system remains constant

• The loss of motion implies a loss of energy from the universe

• Energy was gradually transformed into thermal energy through friction and air resistance

• This is an example of a closed system with ideal conservation

• The system has experienced an energy transformation that cannot be reversed

Which of the following real-life situations involve the principle of conservation of mechanical energy?

• A diver jumping off a 10-meter platform into a swimming pool

• A swinging pendulum in a vacuum chamber

• A compressed spring pushing a block on a frictionless surface

• A satellite losing altitude due to atmospheric drag

• A moving car applying brakes to stop at a red light

Read this case:

"In the rainforest of Costa Rica, a zipline adventure park was designed with a 30-meter-high platform. Visitors slide down 200 meters of cable. Originally, the system used hand-operated braking but later switched to automatic brakes using rubber pads that create friction. Engineers noticed a decrease in final speed compared to the previous design."

What is the best explanation for the decrease in speed using the new system?

• The friction pads increase the thermal energy output of the system

• The system with rubber pads reduces energy loss

• Energy is transformed into sound and heat due to braking

• There is no energy transformation involved

• The mechanical energy is better conserved in the newer system

Based on the truck's sudden braking on the highway, what conclusions can be drawn regarding the mechanical energy involved in the event?

• The truck’s kinetic energy was completely transformed into potential energy as it stopped.

• The kinetic energy of the truck was dissipated primarily as heat due to friction with the road surface.

• The forward motion of the load illustrates inertia and partial energy transfer within the system.

• The fact that the truck took 50 meters to stop suggests that total mechanical energy was conserved.

• Some of the truck’s initial kinetic energy was transformed into deformation energy when the package hit the divider.

Explain how the conservation of energy applies to the braking of the truck and the movement of the cargo. Based on the description, what types of energy transformations are involved, and what does this tell us about the total energy in the system? Support your explanation with specific elements from the scenario.

When a moving object slows down due to friction, part of its mechanical energy is transformed into______

Which of the following systems are most likely to conserve mechanical energy under ideal or nearly ideal conditions?

(Select all that apply)

• A satellite orbiting Earth in the upper atmosphere

• A pendulum swinging in a vacuum

• A compressed spring pushing a block on a lubricated metal surface

• A child sliding down a freshly waxed wooden slide

• A moving bicycle going downhill without pedaling