Frictionless ramp, constant velocity, find work

AI Thread Summary
To calculate the work needed to push a piano weighing 1635.0 kg up a frictionless ramp to a height of 1.73 m, one can apply the principle of conservation of energy. The work done is equivalent to the gravitational potential energy gained by the piano, which is calculated using the formula U = mgh, where m is the mass, g is the acceleration due to gravity (approximately 9.81 m/s²), and h is the height. Since the piano is moved at a constant velocity, all work done translates into potential energy without any losses to friction or acceleration. The resulting work required is significant, reflecting the energy needed to elevate the piano to the truck bed. This approach simplifies the problem by focusing solely on energy changes rather than forces or angles.
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Homework Statement



Movers must push a piano onto a truck, the bed of which is a height 1.73 m above the ground. To do this they will use a frictionless ramp. If the piano has a mass of 1635.0 kg and the movers push it up the slope at a constant velocity, how much work do they need to do on it to move it into the bed? Please provide your answer in kilo-Joules (kJ), as the amount of work should be quite large.


Homework Equations





The Attempt at a Solution


I have no clue where to start here, no angle?
 
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holls14 said:

Homework Statement



Movers must push a piano onto a truck, the bed of which is a height 1.73 m above the ground. To do this they will use a frictionless ramp. If the piano has a mass of 1635.0 kg and the movers push it up the slope at a constant velocity, how much work do they need to do on it to move it into the bed? Please provide your answer in kilo-Joules (kJ), as the amount of work should be quite large.


Homework Equations





The Attempt at a Solution


I have no clue where to start here, no angle?

Do not think of it as a dynamics problem with forces (i.e. you don't need an angle). This is a conservation of energy problem. The work you put into the moving the piano up 1.73 m turns into potential energy. If we think of it in reverse, the potential energy of the piano afterwards is equal to the _______ .

K + U (before) = K + U (after)

where K is kinetic energy and U is potential energy.

K = (1/2)mv2
U = mgh
 
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