Answer:
168.57 mV
Explanation:
Initial magnetic flux = BA , B magnetic field and A is area of loop
= .35 x 3.14 x .37²
= .15 Weber
Final magnetic flux
= - .2 x 3.14 x .37²
= - .086 Weber
change in flux
.15 + .086
= .236 Weber
rate of change of flux
= .236 / 1.4
= .16857 V
= 168.57 mV
The answer is C , you’re welcome
Answer:
a) 1450watts
b) 564watts
c) 1.11
Explanation:
Power consumed = IV
I is the current rating
V is the operating voltage
If a blow-dryer and a vacuum cleaner each operate with a voltage of 120 V and the current rating of the blow-dryer is 12 A, while that of the vacuum cleaner is 4.7 A then their individual power rating is calculated thus;
a) For blow-dryer
Operating voltage = 120V
Its current rating = 12A
Power consumed = IV
= 120×12
= 1440watts
b) For vacuum cleaner:
Operating voltage is the same as that of blow dryer = 120V
Its current rating = 4.7A
Power consumed = IV
= 120×4.7
= 564watts
c) Energy used = Power consumed × time taken
Energy used = Power × time
Energy used by blow dryer = 1440×20×60
= 1,728,000Joules
Energy used up by vacuum cleaner = 564×46×60
= 564×2760
= 1,556,640Joules
Ratio of the energy used by the blow-dryer in 20 minutes to the energy used by the vacuum cleaner in 46 minutes will be 1,728,000/1,556,640 = 1.11
The answer is definitely C.) their molecules move at the same average speed
