Table tennis and air resistance

AI Thread Summary
A table tennis ball with a mass of 10g is falling at a constant speed of 8.2m/s, indicating that the forces acting on it are balanced. The air resistance force must equal the gravitational force acting on the ball, preventing any acceleration. Since the ball is in uniform motion, the net force is zero, confirming that no net accelerating force is present. The discussion emphasizes the relationship between constant speed and the balance of forces, particularly air resistance and gravity. Understanding these dynamics is crucial for solving the problem of calculating air resistance.
Michael17
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Could anyone please explain to me how to work the following question out?

A table-tennis ball of mass 10g is falling towards the ground with a constant speed of 8.2m/s. Calculate the magnitude and direction of the air resistance force acting on the ball.
 
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Shouldn't the ball be accelerating at g? But it falls at constant speed, huh?
 
What forces are acting on the ball? Since it is in uniform motion, the acceleration and total force are obvious. Should be easy to find the unknown force of air resistance!
 
vivesdn said:
Shouldn't the ball be accelerating at g? But it falls at constant speed, huh?

If the speed is constant doesn't it mean to you that there is no net accelerating force?
 

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