A resistor and a capacitor are connected in series across an ideal battery having a constant voltage across its terminals. (a) At the moment contact is made with the battery the voltage across the capacitor is A resistor and a capacitor are connected in series across an ideal battery having a constant voltage across its terminals. (b) At the moment contact is made with the battery the voltage across the capacitor is greater that the battery's terminal voltage. equal to the battery's terminal voltage. less than the battery's terminal voltage, but greater than zero. zero.

The question is not complete. see the complete question in the explanation section. The correct option is highlighted in bold

Explanation:

(a)A resistor and a capacitor are connected in series across an ideal battery having a constant voltage across its terminals. At the moment contact is made with the battery, the voltage across the resistor is

I.     greater than the battery's terminal voltage.  

II.    equal to the battery's terminal voltage.  

III.  less than the battery's terminal voltage, but greater than zero.  

IV.  zero.

Option (i) is not correct as the voltage across the resistor cannot be greater than the terminal voltage since the current is yet to flow through the resistor. Option (ii) is correct as both the resistor voltage and the terminal voltage will just equal at the instance of connection. Option (ii) can only be possible after the current must have passed through the resistor for a while not immediately after contact. Option (iv) is not correct, as this can only be possible is the contact is open.

(b)A resistor and a capacitor are connected in series across an ideal battery having a constant voltage across its terminals. At the moment contact is made with the battery the voltage across the capacitor is  

I.   greater than the battery's terminal voltage.  

II.  equal to the battery's terminal voltage.  

III.less than the battery's terminal voltage, but greater than zero.  

IV.zero.

Option (i) is not correct as the capacitor is yet to charge talk less of the its voltage exceeding that of the battery. Option (ii) can only be correct if the capacitor is fully charged not when it has just been connected. Option (iii) can only occur if the capacitor is discharging. Option (iv) is the correct answer as the capacitor is about to start charging

heat the gas and measure the pressure