Only two forces act on a 3.0-kg mass. One of the forces is 9.0 N east, and the other is 8.0 N in the direction of 62$\degree$ north of west. What is the magnitude of the acceleration of the mass?
A)2.0 m/s2
B)2.4 m/s2
C)3.3 m/s2
D)2.9 m/s2
E)5.7 m/s2

Question

Quizplus · Accepted Answer

The correct answer is D.The magnitude of the acceleration of the mass is 2.9 m/s2.The x-component of the force is 9.0 N east, and the y-component of the force is 8.0 N north.The magnitude of the force is:$$F = \sqrt{9.0^2 + 8.0^2} = 12.0 N$$The direction of the force is:$$	heta = 	an^{-1}\left(\frac{8.0}{9.0}ight) = 42.3\degree$$The acceleration of the mass is:$$a = \frac{F}{m} = \frac{12.0 N}{3.0 kg} = 2.9 m/s^2$$

Only Two Forces Act on a 3 °\degree° North of West

Only Two Forces Act on a 3 $\degree$ North of West