Levers -practical
That's a lot of torque
You often hear racing car enthusiasts talk about torque. A torque is produced when a force causes something to turn. When car enthusiasts talk about the amount of torque they refer to the strength of the turning motion of the wheels. You may have experienced torque when playing on a see-saw, it is the turning motion that each person sitting on opposite ends produces. If one person produces more torque than the other the see-saw rotates.
We will investigate the torque produced on both sides of a balanced lever.
Aim - To see how torque changes as the force (weight) and distance from the fulcrum are altered.
Apparatus - solid, inflexible meter ruler, set of weights, a circular rod.
Method
- balance the meter ruler on the small circular rod.
- move the set of weights on the right to a distance of 25 cm from the fulcrum and once again adjust the weights on the right so that both sides are balanced.
Distance of load(A) from fulcrum (cm) |
Load (g) |
Distance of effort (B) from fulcrum (cm) |
Effort (g) |
| 10 | 50 | ||
| 10 | 50 | ||
| 10 | 50 | ||
| 10 | 50 | ||
| 10 | 50 |
What do you notice happens to the weight needed to balance 50 g, on the left of the ruler, as this weight moves further from the fulcrum?
Could I balance the 50g weight with a 5 gram weight? Explain how.
When the ruler is balanced what do you notice when you multiply the distance by the weight?
When the ruler is balanced the pair of torques on both sides of the fulcrum are balanced. Is there any relationship between weight and distance that you can see from your table of results.
