How much work is done in raising a 50 kg crate a distance of 1.5 m above a store room floor?

Question

(a) How much work is done in raising a 50 kg crate a distance of 1.5 m above a store room floor? (b) What is the change of potential energy as a result of this move? (c) How much kinetic energy will the crate have as it falls and hits the floor?

Answer 1

work = force x distance

50 kg is the measure of the crate's mass. You need to multiply the gravitational constant g = 9.81 m/s^2

Force of crate = mass x g = 50 kg x (9.81 m/s^2) = 490.5 N

Newtons is the unit of force.

a) work = force x distance

490.5 N x 1.5 m = 735.75 Nm (Newton meters)

b) Change in potential energy

You said the crate was on the floor. Since the crate was on the floor, which is y=0, there was no potential energy. When you raised the crate, you added potential energy.

Potential energy = (mass x g) x Height of crate

PE= (50kg x 9.81m/s^2) x 1.5 m = 735.75 Nm

The unit Nm (newton meters) is equivalent to a Joule (J) which is the unit of energy.

so,

PE = 735.75 J

C. Kinetic Energy is defined as .5 x mass x (velocity)^2

= 1/2mv^2

You didn't give a velocity, so you cant solve for this one.

Answer 2

means power is given via: U=m*g*h the place m=merchandise mass, g=acceleration by way of gravity (-9.8m/s^2), and h=top of the article. many times speaking, this undertaking is moving the mass from h1 to h2 (the place h1=0 and h2=a million.5m). subsequently deltaU=U2-U1 deltaU=m*g*h2-m*g*h1 deltaU=m*g*(h2-h1) deltaU=m*g*(a million.5-0) deltaU=50*-9.8*a million.5 deltaU=-735 J Now, the paintings you probably did (stress you utilized) to the crate grow to be interior an identical path as its action, so which you already know that the paintings completed grow to be effective. W=-U W=735 J Kinetic power is often effective, and is comparable to the replace in means on the way down. subsequently KE=-U, or KE=735J the different posters have not tried to reconcile their indicators.

Answer 3

You should have been here a couple of days ago when I worked that exact same problem for somebody else (probably someone in your class)
Work done is 735 J
Ep change is 735 J
Ek will be 735 J

Doug