Question

You pull a 70-kg crate at an angle of 30° above the horizontal. If you pull with a force of 600N and the coefficient of kinetic friction is .4, how far will it move in 3 seconds?

Answer 1

Answer:

Explanation:

Force of friction acting on the body = μ mg cosθ

= .4  x 70 x 9.8 x cos30

= 237.63 N

component of weight = mgsinθ

= 70 x 9.8 x sin30

= 343 N  

Net upward force = 600 - mgsinθ - μ mg cosθ

= 600 - 343 - 237.63

= 105.37 N

acceleration in upward direction = 105.37 / 70

= 1.5 m /s²

s = ut + 1/2 a t²

= 0 + .5 x 1.5 x 3²

= 6.75 m .