The heating element on an electric iron has a resistance of 24 ohm and draws a current of 5.0 A. How much work is done if the iron is used for 45 minutes?

1620000J

Explanation:

Given parameters:

Resistance  = 24ohm

Current  = 5A

Time  = 45min

Unknown:

Work done = ?

Solution:

Electrical work done is given as the product of power with time;

  Electrical work done  = power x time

     Power  = I²R

 Electrical work done  = I²R x time

Convert the given time to seconds;

          1min  = 60s

          45 min  = 45 x 60  = 2700s

Now,

  Work done  = 5² x 24 x 2700 = 1620000J

hey , the answer is c

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg