Question

The shorter, thicker vertical line in the symbol of a cell represents:
A. the positive terminal
B. the negative terminal
C. the direction of current
D. all of these

Answer 1

Hint: Remember that the symbol of an electric cell consists of two terminals. We shall recall that the terminals are represented by lines. One of those lines is long and thin and the other short and thick. One represents the positive terminal and the other represents the negative.

Complete answer:
We know that the representation of a cell is quite simple. It consists of just two terminals. One of the terminals is represented by a thin and long line, but the other terminal is represented by a short and thick line.

The terminal represented by the thin, long line is the positive terminal and the terminal represented by the short thick line is the negative terminal.
So, the answer to the given question is option B negative terminal.

Additional information:
Now let us analyze two very simple circuit diagrams consisting of a cell, bulb and a switch that is connected by wires.
First, let us look at the open circuit,

In this circuit the switch is kept in open condition, so current doesn’t flow in this circuit. Hence, the bulb doesn’t glow.
Now, let us look at a closed circuit that has a current flow in it.

Here, the switch is in closed condition and hence the circuit is complete. So, there is a current flow and also the bulb glows.
By connecting the positive terminal of a cell to the negative terminal of another cell, that is, connecting two cells in series, you could make a battery.

Among the effects caused due to electric current, two are really important- magnetic effect and heating effect. You may have heard of them.
A magnetic field is generated when current flows through a circuit. This effect is used in electric lifts, electric bells, electric fans, etc and hence important in our daily life.
Current flow in wires generates heat in them and this effect is used in electric heaters, electric iron, light bulbs, etc. A fuse is a device used to limit current flow in a circuit and protects from damages and possible fires, and hence it is a safety device which is also based on this effect.

Note: There is an interesting fact on the direction of current flow. Though the electrons move from negative terminal to positive terminal we represent the current flow as per the flow of positive charges by convention. That is, current flow in a circuit is represented as that from long thin terminal to short thick one.