A hoist motor does 3000 J of work raising a pallet, and the lift takes 60 s.
What is the motor's power?
Start with the numbers: W = 3000 J, t = 60 s.
3000 ÷ 60 = 50. The motor transfers 50 J each second: its power is 50 W.
That move is the equation you have: P = W/t.
Finding a power is a routine, and the same three steps work every time.
Step 1: write down the values in the question, and mark the unknown.
Step 2: write down the equation.
Step 3: substitute in the values, and calculate. The result line carries its unit: watts.
A hoist motor does 3000 J of work in 60 s. Calculate its power.
Write down the values in the question:
W = 3000 J, t = 60 s; P = ?
Write down the equation:
P = W/t
Substitute in the values, and calculate:
P = 3000 ÷ 60 = 50
The motor's power is 50 W.
A window motor does 500 J of work closing a skylight in 20 s. Enter the motor's power in watts.
A conveyor motor does 1600 J of work moving boxes in 20 s. Calculate its power.
Write down the values in the question:
W = 1600 J, t = 20 s; P = ?
Write down the equation:
P = W/t
Substitute in the values, and calculate:
P = 1600 ÷ 20 = 80
The conveyor motor's power is 80 W.
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