A voltemeter of resitance `400 Omega` connected for measurement to a section of a ciruit having a resistance of 20 ohm shows a reading of 100 V. What is the error in the reading of the voltmeter, if the current in the main circit is assumed to remain constant before and after connecting the voltmeter?

A voltemeter reads up to 3 V. It resistance is 200 ohm. It is to be used to measure a potential difference, which may be as large as 60 V. What measures you would take to protect the voltmeter?

A voltmeter reads upto 3V. Its resistance is 200 Ohm. It is to be used to measure a potential difference which may be as large as 60V. What measure you would take to protect the voltmeter ?

A galvanometer of resistance G is converted into a voltmeter to measure upto V volts by connecting a resistance R_1 in series with the coil. If a resistance R_2 s connected in series with it then it can measure upto V/2 volts Find the resistance R, in terms of R_1 and R_2 required to convert it into a voltmeter that can read upto 2V volts.

There is a potentiometer wire of length 1200 cm and 60 mA current is flowing in it. A battery of emf 5V and internal resistance of 20 ohm is balanced on potentiometer wire with balancing length 1000 cm. if a voltmeter is connected across the cell, the balancing length decreasing by 20 cm find reading of the voltmeter

A galvanometer can measure a current up to 20 milliampere. When it is connected in series with a resistance of 2,970 ohm, it can read upto 60 volt. The galvanometer has a resistance

In an experiment oh Ohm's law ,the reading of voltmeter across resistor is 15.0 V and reading of current is 0.20 A .The resistance of the resistor in correct significant figure is :

Two resistances of 400 ohm and 800 ohm are connected in series with 6 volt battery of negligible internal resistance. A voltmeter of resistance 10,000ohm is used to measure the potential difference across 400 ohm. The error in the measurement of potential difference in volt approximately .

In a circuit shown in the figure voltmeter reads 30 V, when it is connected across 400 ohm resistance. Calculate what the same votlmeter will read, when connected across the 300 ohm resistance?