1
COMEDK 2020
MCQ (Single Correct Answer)
+1
-0

To the potentiometer wire of length L and 10$$\Omega$$ resistance, a battery of emf 2.5 V and a resistance R are connected in series. If a potential difference of 1 V is balanced across L/2 length, the value of R in $$\Omega$$ will be

A
1
B
1.5
C
2
D
2.5
2
COMEDK 2020
MCQ (Single Correct Answer)
+1
-0

An electron moves with speed of 2 $$\times$$ 10$$^5$$ m/s along the positive x-direction in a magnetic field $$B = (\widehat i - 4\widehat j - 3\widehat k)\,T$$. The magnitude of the force (in N) experienced by the electron is

A
1.18 $$\times$$ 10$$^{-13}$$
B
1.28 $$\times$$ 10$$^{-13}$$
C
1.6 $$\times$$ 10$$^{-13}$$
D
1.72 $$\times$$ 10$$^{-13}$$
3
COMEDK 2020
MCQ (Single Correct Answer)
+1
-0

A horizontal overhead power line carries a current of 90 A in East to West direction. What is the magnitude and direction of the magnetic field due to the current, 1.5 m below the line?

A
1.2 $$\times$$ 10$$^{-5}$$ T, towards South
B
1.2 $$\times$$ 10$$^{-5}$$ T, towards North
C
1.2 $$\times$$ 10$$^{-5}$$ T, towards East
D
1.2 $$\times$$ 10$$^{-5}$$ T, towards West
4
COMEDK 2020
MCQ (Single Correct Answer)
+1
-0

A moving coil galvanometer has 28 turns and area of coil is $$4\times 10^{-2}$$ m$$^2$$. If the magnetic field is 0.2 T, then to increase the sensitivity by 25% without changing area and field, the number of turns should be changed to

A
24
B
35
C
60
D
54
EXAM MAP
Medical
NEETAIIMS
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
Staff Selection Commission
SSC CGL Tier I
CBSE
Class 12