1
COMEDK 2022
MCQ (Single Correct Answer)
+1
-0

Choose the incorrect statements.

A
Silicon is used in the fabrication of LED.
B
LED works on the principle of electroluminescence.
C
LED is a power efficient device.
D
LED is fabricated with direct band gap semiconductor.
2
COMEDK 2022
MCQ (Single Correct Answer)
+1
-0

Charge on electron is

A
3.2 $$\times$$ $$10^{-19}$$ C
B
1.6 $$\times$$ $$10^{-19}$$ C
C
$$-1.6$$ $$\times$$ $$10^{-19}$$ C
D
$$-3.2$$ $$\times$$ $$10^{-19}$$ C
3
COMEDK 2022
MCQ (Single Correct Answer)
+1
-0

Two charged spheres of $$-20\mu$$C and $$60\mu$$C are kept at a certain distance. They are touched and kept again at the same distance. What is the ratio of force experienced before and after?

A
1 : 3
B
3 : 1
C
2 : 1
D
1 : 2
4
COMEDK 2022
MCQ (Single Correct Answer)
+1
-0

The AC voltage across a resistance can be measured using a

A
hot wire voltmeter
B
moving coil galvanometer
C
potential coil galvanometer
D
moving magnetic galvanometer
EXAM MAP