Class 9 Physics - Archimedes Principle

Aim

To verify Archimedes' principle, which states that when a body is partially or completely immersed in a fluid, it experiences an upward buoyant force equal to the weight of the displaced fluid.

Materials Required

• Spring balance (for measuring weight)
• Overflow can (to collect displaced water)
• Beaker (to collect and measure displaced water)
• Solid object (such as a metal or wooden block)
• Water

Image Reference

Procedure

1. Measure the weight of the object in air using the spring balance. Record the weight as W_air.
2. Submerge the object completely in water, making sure that the object does not touch the sides or bottom of the container. Measure the apparent weight of the object using the spring balance. Record this weight as W_water.
3. Fill the overflow can with water and submerge the object in it. The displaced water will overflow from the can into the beaker.
4. Measure the volume of the displaced water by collecting it in the beaker. Record the weight of the displaced water as W_displaced.
5. Compare the loss in weight of the object in water (W_air - W_water) with the weight of the displaced water (W_displaced).

Observation

The weight of the displaced water is found to be equal to the loss in weight of the object when submerged in water. This verifies Archimedes' principle.

Precautions

• Ensure that the object is fully submerged in water, without touching the sides or bottom of the container.
• Use a calibrated spring balance to get accurate weight measurements.
• Ensure that the overflow can and beaker are free of air bubbles, which could affect the accuracy of measurements.

Conclusion

The experiment confirms Archimedes' principle, as the weight of the displaced water is equal to the loss of weight of the object when immersed in water. This demonstrates the buoyant force acting on the object.

Video Reference