Electric Charges and Fields — Physics STD 12 Science — Question

A charge of magnitude 3e  and mass 2m is moving in an electric field . The acceleration imparted to the charge is

(a) 2Ee/3m

(b) 3Ee/2m

(c) 2m/3Ee

(d) 3m/2Ee

Cyclotron is used to accelerate

(a) Electrons

(b) Neutrons

(c) Positive ions

(d) Negative ions

If length of a conductor is doubled and cross-section is made half, then the specific resistance of the substance of changed wire will become:

Vibration magnetometer works on the principle of

(a) Torque acting on the bar magnet

(b) Force acting on the bar magnet

(c) Both the force and the torque acting on the bar magnet

(d) None of these

A magnetic field exerts no force on:

In which of the following systems will the wavelength corresponding to n = 2 to n = 1 be minimum?

The magnetic field lines due to a bar magnet are correctly shown in

(a)

(b)

(c)

(d)

Anti-particle of proton is:

In the adjoining circuit, the e.m.f. of the cell is 2 volt and the internal resistance is negligible. The resistance of the voltmeter is 80 ohm. The reading of the voltmeter will be

(a) 0.80 volt

(b) 1.60 volt

(c) 1.33 volt

(d) 2.00 volt