A man pushing a crate of mass m-92.0 kg at a speed of v-0.875 m/s encounters a r

Question

A man pushing a crate of mass m-92.0 kg at a speed of v-0.875 m/s encounters a rough horizontal surface of length friction between the crate and rough surface is 0.354 and he exerts a constant horizontal force of 292 N on the crate = 0.65 m as in the figure below. If the coefficient of kinetic (a) Find the magnitude and direction of the net force on the crate while it is on the rough surface. magnitude direction !--Select… IN (b) Find the net work done on the crate while it is on the rough surface (c) Find the speed of the crate when it reaches the end of the rough surface. m/s

Explanation / Answer

(a)

By F(net) = F(applied) - F(friction)
=>F(n) = 292 - µ x mg
=>F(n) = 291 - 0.354 x 92 x 9.8
=>F(n) = - 28.16 Newton

-ve indicating that it is a retarding force i.e. opposite the direction of motion

(b) W = F(n) x s
=>W = 28.16 x 0.65 = 18.30 J

(c) By F = ma
=>28.16 = 92 x a
=>a = 0.306 m/s^2
By v^2 = u^2 - 2as
=>v^2 = (0.875)^2 - 2 x 0.306 x 0.65

=>v = 0.606 m/s

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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