Electrostatics — Physics STD 12 Science — Question

What is the resistance of a carbon resistance which has bands of colours brown, black and brown

In the context of Doppler effect in light, the term ‘red shift’ signifies (a) Decrease in frequency(b) Increase in frequency(c) Decrease in intensity(d) Increase in intensity

An electroscope is used:

When connected across the terminals of a cell, a voltmeter measures 5V and a connected ammeter measures 10 A of current. A resistance of 2 ohms is connected across the terminals of the cell. The current flowing through this resistance will be(a) 2.5 A(b) 2.0 A(c) 5.0 A  (d) 7.5 A

A freshly prepared radioactive sample of half- life 1 hour emits radiations that are 128 times as intense as the permissible safe limit. The minimum time after which this sample can be safely used is(a) 14 hours(b) 7 hours(c) 128 hours(d) 256 hours

When a particle travels, then a wave is linked with the particle. The wavelength of the wave is expressed as :

Which material sheet should be placed between the plates of a parallel plate condenser in order to increase its capacitance ?

The rays parallel and close to the principal axis are called:

Two electric bulbs (60W and 100W respectively) are connected in series. The current passing through them is(a) More in 100W bulb(b) More in 60W bulb(c) Same in both(d) None of these

When a copper voltameter is connected with a battery of e.m.f. 12 volts. 2 gms of copper is deposited in 30 minutes. If the same voltameter is connected across a 6 volt battery, then the mass of copper deposited in 45 minutes would be(a) 1 gm(b) 1.5 gm(c) 2 gm(d) 2.5 gm