Activity 7.4 Let us investigate to demonstrate how a lever can lift a heavier object. Class 9

Activity 7.4 Let us investigate to demonstrate how a lever can lift a heavier object. Class 9

Activity 7.4 Let us investigate

Aim: To demonstrate how a lever can lift a heavier object with the lighter force.

Procedure:

1. Take one 30 cm long scale, one pencil, eraser and one stapler.
2. Place the scale over the pencil such that pencil is close to one end of the scale.
3. Place the stapler on the end of scale close to pencil and place the eraser on other end of scale. Heavy stapler can be easily lifted by lighter eraser.

Observation: By applying small force at one end of lever, larger force can be applied to load on the other end of lever. It reduces the force required to lift an object.

1. By applying small force at one end of lever, larger force can be applied to load on the other end of lever. It reduces the force required. It is used to lift heavy objects.

Conclusion: The lever works on the principle: Effort × Effort arm = Load × Load arm

1. By increasing the effort arm, less effort is needed to overcome a large load. MA = effort arm / load arm.