Calculating Student Power: P=W/T Equation Explained | 60kg Lift in 4 Seconds"

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To calculate the power of a student lifting 60kg to a height of 2.5 meters in 4 seconds, the power equation P = W/T is used. Work (W) is determined by the formula W = F × D, where F is the force due to gravity (F = mg). The force required to lift the object is calculated using the gravitational acceleration (9.8 m/s²), leading to a force of 588 N for a 60kg mass. After calculating work and dividing by time, the power output can be determined. Understanding these calculations is essential for accurately assessing the student's lifting power.
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Homework Statement


How powerful is a student who can lift 60kg from the floor to above their head (2.5 meters from the ground) in 4 seconds?


Homework Equations


To find power we would use the equation
P= W/T

The Attempt at a Solution


I'm not sure if we would use the P=w/t equation, and work is an unknown variable, and when I try to find W, W=FxD, Force is also an unknown variable
 
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What is the force on the object due to gravity (this would also be the force required to lift it)?
 


Would the force on the object due to gravity be 9.8N
so the Force required to lift it is 9.8 N
 


Force due to gravity is mg. Then use that and the distance to find the work, and the work and the time to find the power.
 
Last edited:


Keep in mind that the force by gravity is not 9.8 N but rather m(9.8 m/s^2) where 9.8 = g. This would be different if we were on a planet other than our homely earth.
 
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