1
JEE Main 2020 (Online) 6th September Morning Slot
+4
-1
An electron is moving along +x direction with a velocity of 6 $$\times$$ 106 ms–1. It enters a region of uniform electric field of 300 V/cm pointing along +y direction. The magnitude and direction of the magnetic field set up in this region such that the electron keeps moving along the x direction will be :
A
3 $$\times$$ 10–4 T, along –z direction
B
5 $$\times$$ 10–3 T, along –z direction
C
5 $$\times$$ 10–3 T, along +z direction
D
3 $$\times$$ 10–4 T, along +z direction
2
JEE Main 2020 (Online) 6th September Morning Slot
+4
-1
A particle of charge q and mass m is moving with a velocity $$- v\widehat i$$ (v $$\ne$$ 0) towards a large screen placed in the Y - Z plane at a distance d. If there is a magnetic field $$\overrightarrow B = {B_0}\widehat k$$ , the maximum value of v for which the particle will not hit the screen is :
A
$${{2qd{B_0}} \over m}$$
B
$${{qd{B_0}} \over {3m}}$$
C
$${{qd{B_0}} \over {2m}}$$
D
$${{qd{B_0}} \over {m}}$$
3
JEE Main 2020 (Online) 5th September Evening Slot
+4
-1
The quantities x = $${1 \over {\sqrt {{\mu _0}{\varepsilon _0}} }}$$, y = $${E \over B}$$ and z = $${l \over {CR}}$$ are
defined where C-capacitance, R-Resistance, l-length, E-Electric field, B-magnetic field and $${{\varepsilon _0}}$$, $${{\mu _0}}$$, - free space permittivity and permeability respectively. Then :
A
Only y and z have the same dimension
B
x, y and z have the same dimension
C
Only x and y have the same dimension
D
Only x and z have the same dimension
4
JEE Main 2020 (Online) 5th September Evening Slot
+4
-1
An iron rod of volume 10–3 m3 and relative permeability 1000 is placed as core in a solenoid with 10 turns/cm. If a current of 0.5 A is passed through the solenoid, then the magnetic moment of the rod will be :
A
5 $$\times$$ 102 Am2
B
0.5 $$\times$$ 102 Am2
C
500 $$\times$$ 102 Am2
D
50 $$\times$$ 102 Am2
JEE Main Subjects
Physics
Mechanics
Electricity
Optics
Modern Physics
Chemistry
Physical Chemistry
Inorganic Chemistry
Organic Chemistry
Mathematics
Algebra
Trigonometry
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