What is the direction of ‘g’ in Gravitation – Class 9 Science Experiment
Chapter Name: Gravitation
Activity Name: What is the direction of ‘g’ in Gravitation
Activity Description:

The experiment aims to understand the direction of free-fall acceleration (‘g’) by observing the motion of a vertically thrown stone.
Students will measure the time it takes for the stone to return to the Earth’s surface using a stop clock and analyze its speed during upward and downward motion.
Required Items:
- Stop clock or timer
- Stone or any small object for throwing
Step by Step Procedure:
- Find an open area with enough space to safely throw the stone vertically.
- Hold the stone at a comfortable height and throw it directly upwards as vertically as possible.
- Start the stop clock as soon as the stone leaves your hand.
- Observe the stone’s motion as it moves up and then comes back down to the Earth’s surface.
- Stop the timer as soon as the stone touches the ground.
- Record the time taken for the entire motion.
Experiment Observations:
- Note the time taken for the stone to go up and return to the surface.
- Observe the change in speed as the stone moves up and then down.
Precautions:
- Ensure there are no obstacles or people in the path of the thrown stone.
- Be cautious while throwing the stone to avoid any accidents.
- Conduct the experiment in an open area away from fragile or valuable objects.
Lesson Learnt from Experiment:
Through this experiment, students will understand that the free-fall acceleration (‘g’) is always directed vertically downwards. They will also observe that the speed of the stone decreases while moving up and increases while moving down, demonstrating the consistent nature of gravitational force.