Question

An electric heater runs for 15 minutes with a current of 2A.What is the potential difference across the electric heater if it’s transfer 2.16x10^4 J of energy ?

Answer 1

To solve this problem, we can use the formula:

Energy (J) = Power (W) * Time (s)

We know that the power (P) is equal to the product of the current (I) and the potential difference (V):

Power (P) = Current (I) * Potential Difference (V)

Since the heater runs for 15 minutes, we need to convert this time into seconds:

Time (15 minutes) = 15 minutes * 60 seconds/minute = 900 seconds

Given that the current is 2A and the energy transferred is 2.16x10^4 J, we can set up and solve the equations:

Energy (2.16x10^4 J) = Power (2A * Potential Difference (V)) * Time (900 seconds)

Rearranging the equation to solve for potential difference (V):

Potential Difference (V) = Energy (2.16x10^4 J) / (Power (2A) * Time (900 seconds))

Potential Difference (V) = 2.16x10^4 J / (2A * 900 seconds)

Now, we can calculate the potential difference:

Potential Difference (V) = 12 V

Therefore, the potential difference across the electric heater is 12 volts.