a) A crate containing 40 bricks is raised by a forklift through a height of 1.3m

Question

a) A crate containing 40 bricks is raised by a forklift through a height of 1.3m to place on a truck bed. Determine the potential energy gained by the crate if each brick has a mass of 1.3kg.

b) The crate is then pulled by a hoist a distance of 3.4m across the flat trunk bed in 8 seconds. Determine the work done in moving the crate and the power of the hoist when the coefficient of friction is 0.6.

c) The loaded truck of mass 3800kg travels at 20 m/s on its journey. How much kinetic energy does the truck have at this point?

please break the formulas down in simple form with full meanings.

Explanation / Answer

A)

mass of each brick = 1.3 Kg

Height raised     (h)    = 1.3 m

mass of crate (m) = 40* 1.3 Kg= 52 Kg

gain in potential energy = mgh = 52 * 9.8* 1.3 = 662.8 J

B)

Normal force acting on the crate = mg = 52 * 9.8 = 509.6 N

coefficient of friction is 0.6

therefore, frictional force = 0.6 * 509.6 = 305.76 N

workdone by the hoist = force * distance = 305.76 * 3.4= 1039.58 J

Power= wokdone/time = 1039.58/8=129.94W

C)

velocity (v) = 20m/s

mass of truck (m) = 3800 Kg

kinetic Energy = 0.5 *m * v^2 = 0.5 * 3800 * 20 * 20 = 760000Joule =760 KJoule

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

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