0.143 A
Explanation:
The total resistance of the circuit is
so the total current is
Itotal= V/R = 9V/35.89 ohms
= 0.25 A
To find the voltage drop across the 30-ohns resistor, use
V = Itotal × (combined resistance of 40 30)
= 0.25 A × 17.14 ohms = 4.285 volts
so the current through the 30-ohm resistor is
I = (voltage drop)/30-ohms
= (4.285 V)/(30 ohms)
= 0.143 A
Answer : The time required is, 16.1 minutes.
Explanation :
First we have to calculate the amount of heat required to increase the temperature is:
where,
Q = amount of heat required = ?
m = mass
= density of air =
V = volume of air
C = specific heat of air =
= change in temperature =
Now put all the given values in above formula, we get:
Now we have to calculate the time required.
Formula used :
where,
t = time required = ?
Q = amount of heat required =
P = power = 1500 W
Now put all the given values in above formula, we get:
Thus, the time required is, 16.1 minutes.