Action and reaction in Laws Of Motion – Class 9 Science Experiment
Chapter Name: Laws Of Motion
Activity Name: Action and reaction in Laws Of Motion
Activity Description:
This experiment aims to demonstrate action and reaction forces acting on two different objects. The setup involves a test tube filled with a small amount of water and closed with a cork cap.
The test tube is suspended horizontally using two strings. By heating the test tube with a Bunsen burner, the water inside vaporizes and the cork cap blows out. The movement of the test tube and the cork cap is observed and compared, along with the difference in their velocities.
Required Items:
- Test tube (good quality glass)
- Cork cap
- Bunsen burner
- Laboratory stand
- Two strings
Step by Step Procedure:
- Take a test tube of good quality glass and pour a small amount of water into it.
- Place a cork cap at the mouth of the test tube to close it securely.
- Suspend the test tube horizontally using two strings, as shown in Figure 19.
- Heat the test tube using a Bunsen burner until the water inside vaporizes and the cork cap blows out.
- Observe the movement of the test tube and the direction in which it moves. Also, note the direction in which the cork cap moves.
- Compare the velocities of the cork cap and the recoiling test tube.
Experiment Observations:
Upon heating the test tube, the water inside vaporizes, and the cork cap is blown out. The test tube moves in a direction opposite to that of the cork cap. The cork cap exhibits a higher velocity compared to the recoiling test tube.
Precautions:
- Ensure the test tube is made of good quality glass to avoid any accidents.
- Use a laboratory stand to securely suspend the test tube with strings.
- Handle the Bunsen burner with care to prevent any burns or mishaps.
Lesson Learnt from Experiment:
The experiment illustrates Newton’s third law of motion, which states that for every action, there is an equal and opposite reaction. The action force in this case is the water vaporizing inside the test tube, leading to the blowing out of the cork cap.
The reaction force corresponds to the recoil of the test tube in the opposite direction. The experiment highlights the concept of action-reaction pairs and their equal magnitudes but opposite directions.
