An electric hair dryer is rated 350w 110v. the safety fuse in the circuit can withstand 12a of current. how many hair dryers can be safely operated in the circuit?

To determine the number of hair dryers that can be plugged in to a circuit, our basis is the maximum threshold of the current. The current which measures 12 Amperes. This current already incorporates the safety factor that is important in industrial setting.

The voltage and the current can be related to the power by the equation:

P = I*V, where I is the current in Amperes and V is the voltage in volts

Solving for the total power:

P = 12 A * 110 V
P = 1,320 Watts

Since the power rating of each hair dryer is 350 W, we divide this to the total power to determine the capacity.

Number of hair dryers = 1,320 Watts/350 Watts per hair dryer
Number of hair dryers = 3.77

In this case, we cannot round off to 4 because this would already exceed the maximum power capacity. Therefore, the total number of hair dryers allowable is 3.