Work, Energy and Power

Once upon a time, there was a little girl named Nikki who loved to play. She would run and jump and climb all day long. One day, Nikki was playing in the park when she saw a big rock. She wanted to move the rock, but it was too heavy. She tried pushing and pulling, but the rock wouldn’t budge.

Nikki’s father, came over to help. They both pushed and pulled on the rock, but it still wouldn’t move. They were tired and about to give up when Nikki’s father had an idea. He ran to the playground and got a big stick. He used the stick to lever the rock up and over. The rock rolled out of the way, and Nikki and her father were able to pass by.

Nikki asked her father, ” Papa, how come we were able to move the rock with the stick, but we couldn’t move it by ourselves?”

Her father explained, “When we pushed and pulled on the rock, we were doing work. Work is when you use force to move something. But the rock was too heavy for us to move by ourselves. When we used the stick, we were able to use more force. That’s why we were able to move the rock.”

Nikki said, “I see. So, work is using force to move something, and energy is the power to do work. Right?”

Her father said, “That’s right. Energy can be in different forms, like kinetic energy and potential energy. Kinetic energy is the energy of motion. When you’re running or jumping, you have kinetic energy. Potential energy is the energy that something has because of its position. For example, a rock that’s sitting on a hill has potential energy. If it falls, the potential energy will be converted into kinetic energy.”

Nikki said, “That’s so interesting! So, power is how much work you can do in a certain amount of time?”

Her father said, “That’s right. Power is the rate at which work is done. So, a car that can go from 0 to 60 kilometres per hour in 6 seconds has more power than a car that can go from 0 to 60 kilometres per hour in 12 seconds.”

Nikki said, “Wow! I never knew that work, energy, and power were all connected. Thanks for explaining it to me, Papa!”

Her father said, “You’re welcome, Nikki. I’m glad I could help.”

Nikki and her father continued to play in the park, and Nikki learned a lot about work, energy, and power. They had a lot of fun, and they even moved a few more rocks.