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Question
In the following example, try to identify the number of times the velocity of the ball changes:
“A football player kicks a football to another player of his team who kicks the football towards the goal. The goalkeeper of the opposite team collects the football and kicks it towards a player of his own team”.
Also identify the agent supplying the force in each case.
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Solution
- The velocity of the football changes when the first player kicks the ball towards another player on his team.
- The velocity of the football changes when another player kicks it towards the goal.
- The velocity of the football changes as the opposing team's goalkeeper collects it.
- The velocity of the football changes when the goalkeeper kicks it towards a teammate.
Thus, the velocity of the ball changes four times in this case.
In the first and second examples, the players' feet provide force. In the third situation, the goalkeeper's hands deliver force. In the fourth example, the goalkeeper's foot provides force as he smashes the football with his foot.
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