Posted by aly on Thursday, December 2, 2010 at 11:24pm.
A 7.6 kg chair is pushed across a frictionless floor with a force of 42 N that is applied at an angle of 22° downward from the horizontal. What is the magnitude of the acceleration of the chair?

physics  Ann Hiro, Friday, December 3, 2010 at 12:09am
F = MA, right? Just mix in a cos Θ to calculate effective force (42N x cos 22° = 38.94172N), and solve.
38.94172 = 7.6A
A = 38.94172 / 7.6
A = 5.123911m/s^2 
physics  drwls, Friday, December 3, 2010 at 6:13am
a = F_x/m
F_x is the xcomponent of F, 42 cos22 = 38.94 N
AnnHiro is correct. Thanks for helping us out, Ann.
The answer should only be quoted to two significant figures, 5.1 m/s^2. The input numbers have comparable accuracy.