If fuse of 250 mA, 500 mA, 1 A, 5 A and 10 A were available, which one would be the most suitable for protecting an amplifier rated at 240 V, 180 W?
Given,
Power, P = 180 W (Watt)
Voltage, V = 240 V (Volt)
Here, we will first calculate the current (I)
Power, $P=V\times I$
Then, $I=\frac{P}{V}$
$I=\frac{180}{240}$
$I=0.75A$ (Ampere)
The fuse wire should be capable of withstanding only slightly more current than 0.75A.
So the fuse of 1A will be most suitable.
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