Energy question, involving work, there is a missing variable?

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To determine the constant speed of a forklift lifting a 613.0 kg mass with a power output of 950 W, the relationship between power, mass, and gravitational force can be utilized. By rearranging the equation for work (W = mg * d) and dividing by time, the formula simplifies to power (P = mg * v). Substituting the known values of power and mass allows for the calculation of the forklift's velocity. The discussion highlights the importance of understanding how to manipulate equations to find missing variables in physics problems. This approach effectively resolves the issue of not having displacement or time directly provided.
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Homework Statement



A 613.0 kg mass is placed on a forklift that can generate 950 W of power. What is the constant speed of the forlift while lifting this load?

Homework Equations



W = F * change in Displacement ( or (F)(change in displacement)(costheta))

W = mg * Change in displacement

P = W/t
Ekinetic = 1/2mv^2

Work is in joules, power is in Watts.

The Attempt at a Solution



950 W = W/t (I don't have time or displacement)

W = mg * change in displacement
W = (9.5*613 )* change in displacement(which I do not have)
W = 6007.4 N *change in displacement
change in displacement = vAverage * change in time
change in time = all include velocity, which I am looking for.
?

Ekinetic = 1/2mv^2
xJ = (613.0kg/2)v^2
xJ = 306.5v^2
?


I feel like I need displacement or time, but I'm given neither. :\
 
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oddcitations said:
W = F * change in Displacement

Good! Now what happens if you take both sides of this equation, and divide them by t?
 
oddcitations said:

Homework Statement



A 613.0 kg mass is placed on a forklift that can generate 950 W of power. What is the constant speed of the forlift while lifting this load?

Homework Equations



W = F * change in Displacement ( or (F)(change in displacement)(costheta))

W = mg * Change in displacement

P = W/t
Ekinetic = 1/2mv^2

Work is in joules, power is in Watts.

The Attempt at a Solution



950 W = W/t (I don't have time or displacement)

W = mg * change in displacement
W = (9.5*613 )* change in displacement(which I do not have)
W = 6007.4 N *change in displacement
change in displacement = vAverage * change in time
change in time = all include velocity, which I am looking for.
?

Ekinetic = 1/2mv^2
xJ = (613.0kg/2)v^2
xJ = 306.5v^2
?


I feel like I need displacement or time, but I'm given neither. :\

take equation w=mg*d
divide both side by t,then u will get p=mg*v
put the values of p,m&g,so find the velocity of forlift...
 
cepheid said:
Good! Now what happens if you take both sides of this equation, and divide them by t?

Ah...
nikhil khatri said:
take equation w=mg*d
divide both side by t,then u will get p=mg*v
put the values of p,m&g,so find the velocity of forlift...


That is so ingenius, I love it! Thank you guys very much! :]
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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