Question

A crate of mass 9.2 kg is pulled up a rough incline with an initial speed of 1.42 m/s. The pulling force is 94 N parallel to the incline, which makes an angle of 19.6° with the horizontal. The coefficient of kinetic friction is 0.400, and the crate is pulled 4.92 m. (a) How much work is done by the gravitational force on the crate?.

Answer 1

Answer:

W = -148.8 J

Explanation:

given,

mass = 9.2 kg

initial speed = 1.42 m/s

pulling force = 94 N    

angle θ = 19.6°      

coefficient of kinetic friction = 0.400          

the crate is pulled = 4.92 m      

to calculate of work done by the gravitation force

gravitation force            

W = ( m g sin θ ) x                

W = 9.2 × (-9.8) × sin 19.6° × 4.92        

W = -148.8 J            

Work done by the gravitation force is taken as negative because gravitation force act opposite to the force applied.