Does an ammeter have a low or a high resistance?

An electric bulb works on the heating effect of current.

An electric appliance draws a current of $0.4\, A$ when the voltage is $200\, V$. Calculate the amount of charge flowing through it in one hour.

$A$ student carries out an experiment and plots the $V-I$ graph of three samples of nichrome wire with resistances $R_1, R_2$ and $R_3$ respectively (Figure). Which of the following is true?

If $R_{1}$ and $R_{2}$ are the resistances of filaments of a $400 \ W$ and a $200 \ W$ lamp,designed to operate on the same voltage,then

$(a)$ What are the values of $mA$ and $\mu A$ in terms of Ampere $(A)$?
$(b)$ Draw the symbols of a battery and a rheostat.