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Question
Write scientific reasons.
The value of gravitational acceleration (g) is taken to be -g when studying the motion of an object thrown upwards in a straight line.
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Solution
- For the motion of an object thrown upwards, the magnitude of g is the same throughout the motion, but the velocity of the object decreases with the increase in height.
- For an object thrown upwards, the direction of acceleration due to gravity is opposite to the velocity of the object.
Hence, the value of gravitational acceleration (g) is taken to be -g when studying the motion of an object thrown upwards in a straight line.
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