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.
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Solution
The velocity of football changes four times.
First, when a football player kicks a football to another player, second when that player kicks the football to the goalkeeper. Third when the goalkeeper stops the football. Fourth, when the goalkeeper kicks the football towards his team player.
Agent supplying the force:
- a) The First case is the First player
- b) The Second case is the Second player
- c) The Third case is Goalkeeper
- d) The Fourth case is Goalkeeper
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