A warehouse worker is pushing a 90.0-kg crate with a horizontal force of 300 N a

Question

A warehouse worker is pushing a 90.0-kg crate with a horizontal force of 300 N at a speed of v = 0.855 m/s across the warehouse floor. He encounters a rough horizontal section of the floor that is 0.75 m long and where the coefficient of kinetic friction between the crate and floor is 0.352. Awarehouse worker is pushing a 90.0-kg crate with a horizontal force of 300 N at a speed of v 0.855 m/s across the warehouse floor. He encounters a rough horizontal section of the floor that is 0.75 m long and where the coefficient of kinetic friction between the crate and floor is 0.352. (a) Determine the magnitude and direction of the net force acting on the crate while it is pushed over the rough section of the floor. magnitude N direction in the same direction as the motion of the crate (b) Determine the net work done on the crate while it is pushed over the rough section of the floor. (c) Find the speed of the crate when it reaches the end of the rough surface. m/s

Explanation / Answer

a) Kinetic Friction Force f = u.N

and N = mg

so f = 0.352 x mg = 0.352 x 90 x 9.81 = 310.78 N

So Fnet = F - f = 300 - 310.78 = - 10.78 N

Magnitude = 10.78 N

Direction = Opposite diretion of motion

B) Net Work Done = Fnet .d

= -10.78 * 0.75   = - 8.085 J

C ) Using Work energy theorem,

Net work Done= change in K.E.

-8.085 = 90v2 /2 - 90*0.8552 /2

v = 0.742 m/s ...Ans

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.