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Falling under Gravity

  • Thread starter polekitten
  • Start date
  • #1
1. What have I done wrong when I set this GCSE question?! (shortened)
Gravity: 10 N/kg
Bowling ball: weight 10 N, air resistance 0.05 N, overall force 9.95 N
Football: mass 0.5 kg, air resistance 0.05 N

Students need to work out:
  • effective force on the football (4.95 N)
  • bowling ball (a = F/m = 9.95 / 1 = 9.95 N/kg)
  • football (a = F/m = 4.95 / 0.5 = 9.9 N/kg)
So... what have I messed up as I'm pretty sure their acceleration should be equal!?

Homework Equations


F = ma, W = mg

The Attempt at a Solution


I have played around with it and I'm missing something, help!
 

Answers and Replies

  • #2
DrClaude
Mentor
7,339
3,520
So... what have I messed up as I'm pretty sure their acceleration should be equal!?
Why should the acceleration be the same when you take into account air resistance?
 
  • #3
Dumb... thanks for pointing out the obvious!
 

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