If a 2V battery is connected to the wire in one direction, the electrode that was the cathode becomes the anode and vice verse, but when the battery is connected the other way the cathode and anode do not switch. Explain why this is so, and what the voltages of the two situations are.

1. This is so because of the charging and discharging phenomenon of the battery.

2. Voltage when fully charged: approximately 2.15 volts

Voltage when in use: drops below 2.15v

Explanation:

The anode is the electrode where electricity flows into. In contrast, the cathode is the electrode where the electricity flows out of.  When a battery is connected to a load the electricity flows from the positive terminal to the negative terminal. In this case, the positive terminal is the cathode, and the negative terminal is the anode.  Here the cathode and anode do not switch,

But when the battery is being charged, the electricity flows into the positive terminal instead of out of it. In this case, the roles are reversed, the electrode that was the cathode becomes the anode, and the anode becomes that cathode.

A fully charged 2volt battery has a voltage of approximately 2.15 volts. A fully discharged 2 volt battery has a voltage of 1.9 volts

the answer is b, have negligible mass