3.4 Work
Work or Not?
In the following situations, identify whether work is being done (or not).
Example #1:
 |
John is pushing on a huge wall partition. He is sweating and pushing with a big force, but he can't budge it. Is John doing work on the wall? If work is being done, is it converted into potential or kinetic energy? Think about an answer before checking solution. |
Example #2:
 |
David is in training and doing sprints with a parachute. Is David doing work on the parachute during the sprints? If work is being done, is it converted into potential or kinetic energy? Think about an answer before checking solution. |
Example #3:
 |
Sonia is doing a plank for 45 seconds. Is Sonia doing work? If work is being done, is it converted into potential or kinetic energy? Think about an answer before checking solution. |
Example #4:
 |
Carol is bench pressing 85 kg. She does 5 repetitions. Is Carol doing work during her bench pressing? If work is being done, is it converted into potential or kinetic energy? Think about an answer before checking solution. |
Example #5:
 |
Val pulls back a bearing in her new sling shot. Did she do work to get the bearing ready to shoot? If work is being done, is it converted into potential or kinetic energy? Think about an answer before checking solution. |
Example #6:
 |
At the first stage of a roller coaster ride, the roller coaster is pulled up to the top of the first hill. Is there work being done here? If work is being done, is it converted into potential or kinetic energy? Think about an answer before checking solution. |
| Energy in Food |
| One of the mose powerful things about working with energy is that it can be represented in SO many forms. We can even measure the energy within our food. Energy from food is usually measured in joules or calories. |