Can a hot-wire ammeter be used to measure a direct current having a constant value? Do we have to change the graduation?

It is advantageous to use the device having smaller value of least count". Explain the statement.

A direct current of 2 A and an alternating current having a maximum value of 2 A flow through two identical resistances. The ratio of heat produced in the two resistances will be

The diameter of a wire is measured with a screw gauge having least count 0.01 mm . Out of the following the one which correctly expresses its diameter is

How do we know that we have eaten enough ?

Resistance of a given wire is obtained by measuring the current flowing in it and the voltage difference applied across it. If the percentage errors in the measurment of the current and the voltage difference are 3% each, then error in the value of resistance of the wire iS :

_____ rule is used to find the direction of induced current in a conducting wire, moving in a magnetic field.

Which rule can be use to determine direction of magnetic field due to current carrying loop.

A potentiometer having the potential gradient of 2 mV//cm is used to measure the difference of potential across a resistance of 10 ohm . If a length of 50 cm of the potentiometer wire is required to get null point, the current passing through the 10 ohm resistor is (in mA )

The length of a cylinder is measured with a meter rod having least count 0.1 cm . Its diameter is measured with Vernier calipers having least count 0.01 cm . Given that length is 5.0 cm and radius is 2 cm . Find the percentage error in the calculated value of the volume.

The resistance of an ammeter is 13 Omega and its scale is graduated for a current upto 100 A . After an additional shunt has been connected to this ammeter it becomes possible to measure currents upto 750 A by this meter. The value of shunt resistance is