Why are the accelerations of the bowling ball and football not equal?

[polekitten]

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!

 

[DrClaude]

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?

 

[polekitten]

Dumb... thanks for pointing out the obvious!