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3 votes
An electric motor operates a pump that irri-

gates a farmer's crop by pumping 10 000 L of
water a vertical distance of 8.0 m into a field
each hour. The motor has an operating resis-
tance of 22.0 2 and is connected across a
110-V source.
a. What current does it draw?
b. How efficient is the motor?

User Skmathur
by
3.5k points

1 Answer

7 votes

Answer:

a. 5A

b. 39.60%

Step-by-step explanation:

The computation is shown below:

a. The current does it draw is

= v ÷ R

= 110v ÷ 22

= 5A

b. Now the efficiency of the motor is

n = mgh ÷ vlt

= (10,000 × 9.8 × 8) ÷ (5 × 3600 × 110)

= 784000 J ÷ 1,980,000

= 39.60%

hence, the above formulas are applied & the same is relevant

User Lynnjwalker
by
3.2k points