CBSE
Multiple Choice QuestionsA galvanometer coil has a resistance of 15 Ω and gives full-scale deflection for a current of 4 mA. To convert it to an ammeter of range 0 to 6 A
10 mΩ resistance is to be connected in parallel to the galvanometer
10 mΩ resistance is to be connected in series with the galvanometer
0.1 Ω resistance is to be connected in parallel to the galvanometer
0.1 Ω resistance is to be connected in series with the galvanometer
Calculate the current which will produce a deflection of 30° in a tangent galvanometer, if its reduction factor is 3 A.
1.732 A
0.732 A
3.732 A
2.732 A
A solenoid 1.5 m long and 0.4 cm in diameter possesses 10 turns/cm length. A current of 5 A falls through it. The magnetic field at the axis inside the solenoid is
2π × 10-3 T
2π × 10-5 T
4π × 10-2 T
4π × 10-3 T
If the vibrations of a string are to be increased by a factor of two, the tension in the string should be made
twice
four times
eight times
half
A proton and a deuteron with the same initial kinetic energy enters a magnetic field in a direction perpendicular to the direction of the field. The ratio of the radii of the circular trajectories described by them is
1 : 4
1 : √2
1 : 1
1 : 2
A cyclotron can accelerate
β-particles
α-particles
high-velocity gamma rays
high-velocity X-rays
Two identical galvanometers are taken, one is to be converted into an ammeter and other into a milliammeter. The shunt of milliammeter compared to ammeter is
less
more
zero
none of these
What is shape of· magnet in moving coil galvanometer to make the radial magnetic field?
Concave
Horseshoe magnet
Convex
None of the above
A candidate connects a moving coil ammeter A and a moving coil voltmeter V and a resistance R as shown. If the voltmeter reads 20 V and the ammeter reads 4 A, then R is
equal to 5Ω
greater than 5Ω
less than 5Ω
none of these
A charged particle enters in a strong perpendicular magnetic field. Then its kinetic energy
increases
decreases
remains constant
None of these
