A 30 kg water container is lifted to a height of 2 m in 1 minute. How much work is done in lifting the water container? How much power is exerted in the process?
I think it should be zero for both because the container has no horizontal displacement but that doesn't seem right...is it?
Thanks.
weight = mg
work = weight * distance
power = work/time
care to revise your answer?
W = F*d = Mg*d = 30 * 9.8*2 =
P = W/t.
To calculate the work done in lifting the water container, you can use the formula:
Work = Force x Distance x Cos(theta)
In this case, the force can be calculated using Newton's second law:
Force = mass x acceleration
Since the container is being lifted vertically at a constant speed, there is no acceleration (acceleration = 0). Therefore, the force becomes:
Force = mass x 0 = 0
The distance is given as 2 m and the angle theta between the force and displacement is 0 degrees (cos(0) = 1). Substituting these values into the work formula, we get:
Work = 0 x 2 x 1 = 0 Joules
Therefore, the work done in lifting the water container is indeed equal to zero.
Now, let's calculate the power exerted in the process. Power can be calculated using the formula:
Power = Work / Time
Since the work done is zero, dividing by any time value will still yield zero. Thus, the power exerted in lifting the water container is also zero.
In this case, your initial intuition was correct. Since there is no horizontal displacement, no work is done, and therefore no power is exerted.