Finding power without given speed or time

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The discussion revolves around calculating the power developed by a lawn tractor moving up a hill at a constant velocity, given its mass, incline angle, and distance. The user calculated the force down the slope using the formula mgsin(21 degrees), resulting in a force of 421.4 N. However, the lack of a specific velocity or time value prevents a direct calculation of power, leading to the conclusion that a symbolic answer may be necessary. Participants emphasize the importance of ensuring no information has been overlooked that could assist in finding a numerical solution. Ultimately, the situation highlights the challenge of solving physics problems with incomplete data.
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Homework Statement


The lawn tractor in figure 18 goes up a hill at a constant velocity. Calculate the power that is developed by the tractor.
Mass: 120.0 kg
Angle of incline: 21 degrees
Distance: 12.0 m
Velocity: no velocity given other than it is constant
Time: idk

Homework Equations


None really

Just note that I used 9.8ms^-2 for acceleration due to gravity, NO value for velocity was given, and no time value was given.

The Attempt at a Solution


So I calculated the force in the direction of down the slop (by using mgsin21) and got a force of 421.4N, which means, since the acceleration in the dimension of the slope is 0ms^-2, that the net force is zero, meaning that the motor produces 421.4N of force. Now from here I’m stuck, as no value for velocity is given other than that it’s constant, and idk how to calculate time without velocity so that I could calculate power. Pls help.
 
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J51mustang said:
Mass: 120.0 kg
Angle of incline: 21 degrees
Distance: 12.0 m
Constant velocity
If that is all you are given then there is clearly not enough information. Make very sure there is no information you have overlooked. Some detail in the figure, perhaps?
 
Hi J51mustang,

Welcome to Physics Forums!

Since no velocity is given it looks like you'll have to provide a symbolic answer rather than a particular numerical result...
 
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