# A-level Physics question Mechanics

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#1
https://pmt.physicsandmathstutor.com...%20A-level.pdf

um for question 1aiii, when calculating the acceleration, why are we supposed to only use the mass of the glider? I was under the impression that since there is a force upwards, the resultant force downwards is 1000, and then we divide that by 9.81 to get the mass, if that makes any sense?
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2 weeks ago
#2
(Original post by Qxi.xli)
https://pmt.physicsandmathstutor.com...%20A-level.pdf

um for question 1aiii, when calculating the acceleration, why are we supposed to only use the mass of the glider? I was under the impression that since there is a force upwards, the resultant force downwards is 1000, and then we divide that by 9.81 to get the mass, if that makes any sense?
Go back to Newt's 2nd. Net force F = ma. You use the inertial mass m, which is of the glider, not some ethereal quantity like "effective mass" or something else like that (which you consider in buoyancy and other stuff.)
1
1 week ago
#3
(Original post by Qxi.xli)
https://pmt.physicsandmathstutor.com...%20A-level.pdf

um for question 1aiii, when calculating the acceleration, why are we supposed to only use the mass of the glider? I was under the impression that since there is a force upwards, the resultant force downwards is 1000, and then we divide that by 9.81 to get the mass, if that makes any sense
================================ ================================ ===========
Total mass, M = 6500/9.81
resultant force = M x a, you can get a now
1
#4
(Original post by Callicious)
Go back to Newt's 2nd. Net force F = ma. You use the inertial mass m, which is of the glider, not some ethereal quantity like "effective mass" or something else like that (which you consider in buoyancy and other stuff.)
thank you
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