A poetential difference of 200 V is applied to a coil at a temperature of `15^(@)C` and the current is 10 A. What will be the mean temperature of the coil when the current hass fallen to 5 A, the applied voltage being same as before ? Given `alpha=(1)/(234).^(@)C^(-1) " at " 0^(@)C`.

(i) A potential difference of 200 volt is applied to a coil at a temperature of 15^(@)C and the current is 10 A. What will be the temperature of the coil when the current has fallen to 9 A, the applid voltage being the same as before ? Temperature coefficient of resistance (alpha)=1/(234).^(underline(o))C^(-1) . (ii) A platinum wire has resistance of 10 ohm at 0^(@)C and 20 ohm at 273^(@)C . Find the value of temperature coefficient of resistance.

A potential difference of 120 V is applied to a coil at temperature of 12^@C and the current is 6A. What will be the mean temperature of the coil when the curreny has fallen to 3 A, the applied voltage being the same as before ? Given temperature coefficient of resistance coil is .00427^@C^(-1) at 0^@C .

When an alternating voltage of 100V, 50 Hz is applied to a choke coil, it takes a current of 10 A and the power is 500 W. What is the choke coil?

What is the resistance of a relay coil which draws a current of 35 mA when the voltage applied to it is 14 V.

When a potential difference 30V is applied across a resistors, it draws a current of 3A. If 20V is applied across the same resistor, what will be the current ?

200 V AC is applied to primary coil of a transformer and it is found that output current is 8 A and output voltage is 50 V. Assume no energy loss. Find the current in primary coil I ampere.

A heating coil is connected in series with a resistance r. the coil is dipped in a liquid of mass 2kg and specific heat 0.5cal g^(-1) .^(@)C^(-1) . A potential difference of 200V is applied and the temperature of the liquid is found to increase by 60^(@)C in 20 minutes. if R is removed, the same rise in temperature is reached in 15minutes if R is removed, the same rise in temperature is reached in 15 minutes. find the value of R.

A heating coil is connected in series with a resistance r. the coil is dipped in a liquid of mass 2kg and specific heat 0.5cal g^(-1) .^(@)C^(-1) . A potential difference of 200V is applied and the temperature of the liquid is found to increase by 60^(@)C in 20 minutes. if R is removed, the same rise in temperature is reached in 15minutes if R is removed, the same rise in temperature is reached in 15 minutes. find the value of R.

The current through a conductor is 1 ampere when the temperature is 0^(@)C and 0.7 ampere when the temperature is 100^(@)C . What would be current when the temperature of the conductor is 1200^(@)C ?

When an AC signal of frequency 1 kHz is applied across a coil of resistance 100 Omega , then the applied voltage leads the current by 45^@ . The inductance of the coil is