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sakthi vel
Jun 20, 2012, 08:08 AM
An electric geyser is known to consume 2.2 units of electrical energy per hour of its use. It is designed to work on the main voltage of 220V.
1.what is 'power rating' of this device.
2.what is the current flowing through the device when it is connected across the mains
3.what is the resistance of this device

ebaines
Jun 20, 2012, 08:18 AM
an electric geyser is known to consume 2.2 units of electrical energy per hour of its use. it is designed to work on the main voltage of 220V.
1.what is 'power rating' of this device.

Power is measured in energy per unit time. You are told it uses 2.2 "units" of energy per hour, so the power usage should be obvious.



2.what is the current flowing through the device when it is connected across the mains

Power = voltage times current. You have numbers for power and voltage, so you can calculate current.


3.what is the resistance of this device

Use Power = I^2R, or Power = V^2/R, to find the value of R.