A 150 W light bulb is connected to this power source and it glows at its maximum brightness.
Use the information from the graph to calculate the:
6.1 period of the wave?
6.2 frequency of the wave?
6.3 Resistance of the bulb?
6.4 RMS current through the bulb
6.5 The cost of the electricity it uses in 32 hours if 1 kWh costs R2,50.
6.1 To calculate the period of the wave, we need to find the time taken for one full cycle. From the graph, we can see that one cycle takes 0.02 seconds. Therefore, the period of the wave is 0.02 seconds.
6.2 The frequency of the wave is the number of cycles per second. Since one cycle takes 0.02 seconds, the frequency is 1/0.02 = 50 Hz.
6.3 To calculate the resistance of the bulb, we can use the formula P = I^2 * R, where P is the power (150 W) and I is the current. From the graph, we can see that the peak current is approximately 1.2 A. Therefore, the resistance R can be calculated as R = P / I^2 = 150 / (1.2)^2 = 104.17 ohms.
6.4 The RMS current through the bulb can be calculated using the formula Irms = peak current / sqrt(2). From the graph, we found the peak current to be approximately 1.2 A. Therefore, Irms = 1.2 / sqrt(2) = 0.85 A.
6.5 The energy used by the bulb in 32 hours can be calculated as follows:
Energy = Power x Time = 150 W x 32 hours = 4800 Wh = 4.8 kWh
Cost = Energy x Cost per kWh = 4.8 kWh x R2.50/kWh = R12.00
Therefore, the cost of the electricity the bulb uses in 32 hours is R12.00.