When Deepak studied the electrical circuits and the current flowing through them, he became curious about the range of the currents we come across in daily life. He collected the data and presented in a tabular form as shown below. He then studied the instruments used to detect and measure current, however could not understand the difference between an ammeter and an ideal ammeter and thus went to his teacher for the explanation.
S.No. |
Description |
Magnitude of current |
1 |
Domestic Appliance |
Few amperes |
2 |
Lightning |
Ten thousand amperes |
3 |
Nervous system |
microamperes |
4 |
Galvanometer |
Few milliamperes |
5 |
Semiconductors |
Few milliamperes |
(i) What values did Deepak have?
(ii) As domestic appliances carry electric current of the order of few amperes, write one safety precaution we should take while working with them.
(iii) An ammeter of resistance RA is connected in series with a resistor R and a battery of emf E and internal resistance r. The current flowing through this circuit is IA. What will be the current flowing through the circuit if the given ammeter is replaced by an ideal ammeter and find the percentage error in measuring the current through an ammeter?