Try this exciting experiment in the playground with a swing and find out if weight has any effect on the speed of the swing of a pendulum.
Things Required:
Watch
Outside playground swing
Ruler
2 helpers
Directions:
Hold the seat of the swing and move back 3 or 4 steps. Ask your helper to place the ruler on the ground in front of your feet. Ask your helper to start timing when you release the swing and to report the end of 10 seconds.
Caution: Do not push the swing; just release it.
Count the number of swings back and forth in 10 seconds. Ask one of your helpers to sit in the swing. Pull the swing back until your feet are behind the ruler as before. Again, ask your helper to start the timer when you release the swing and report the end of 10 seconds.
Caution: Do not push the swing.
Count the number of back-and-forth swings in 10 seconds.
This Is What Happens:
The number of back-and-forth swings is the same with and without a person sitting in the swing.
Science Behind It:
The number of back-and-forth swings was the same regardless of the weight placed on the swing because gravity pulled on the swing, causing it to fall when released. The speed during the swings changed, but the changes were the same for each weight that was swung. The speed increased as the swing or pendulum approached the vertical position and slowed as it moved upward where it stopped. Pendulums stop at the highest position of their swing before beginning the downward swing (that is due to the pull of gravity). The speed of this back-and-forth movement stays the same for each weight because the beginning height of the swinging path of the pendulum remained the same each time and the downward pull on gravity is the same on all substances regardless of their weight.