An alternating voltage given by
`E = 280 sin 50 pi t` is connected across a pure resistor of 40 ohm. Find frequency of source and rms current through the bulb.

Explanation

To solve the problem step by step, we will follow the given information and apply relevant formulas.

### Step 1: Identify the given information
The alternating voltage is given by the equation:
\[ E = 280 \sin(50 \pi t) \]
We also know that this voltage is connected across a pure resistor of resistance \( R = 40 \, \Omega \).

### Step 2: Determine the amplitude and angular frequency
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