1
KCET 2017
MCQ (Single Correct Answer)
+1
-0
A galvanometer of resistance $50 \Omega$ is connected to a battery of $3 \cdot \mathrm{~V}$ along with a${ }^{\text { }}$ resistance of $2950 \Omega$ in series shows full-scale deflection of 30 divisions. The additional series resistance required to reduce the deflection to 20 divisions is
A
$2950 \Omega$
B
$1500 \Omega$
C
$4440 \Omega$
D
$7400 \Omega$
2
KCET 2017
MCQ (Single Correct Answer)
+1
-0

In the A.C. circuit shown, keeping ' $K$ ' pressed, if an iron rod inserted into the coil, the bulb in the circuit,

KCET 2017 Physics - Alternating Current Question 4 English
A
glows less brightly
B
glows with same brightness (as before the rod is inserted)
C
gets damaged
D
glows more brightly
3
KCET 2017
MCQ (Single Correct Answer)
+1
-0
A magnetic dipole of magnetic moment $6 \times 10^{-2}$ A-m ${ }^2$ and moment of inertia $12 \times 10^{-6} \mathrm{~kg}-\mathrm{m}^2$ performs oscillations in a magnetic field of $2 \times 10^{-2} \mathrm{~T}$. The time taken by the dipole to complete 20 oscillations is ( $\pi \approx 3$ )
A
18 s
B
6 s
C
36 s
D
12 s
4
KCET 2017
MCQ (Single Correct Answer)
+1
-0
$4 \times 10^{10}$ electrons are removed from a neutral metal sphere of diameter 20 cm placed in air. The magnitude of the electric field (in $\mathrm{NC}^{-1}$ ) at a distance of 20 cm from its centre is
A
640
B
5760
C
Zero
D
1440