1
MHT CET 2020 19th October Evening Shift
MCQ (Single Correct Answer)
+1
-0

An electron moves in a circular orbit with uniform speed $v$. It produces a magnetic field $B$ at the centre of the circle. The radius of the circle is [ $\mu_0=$ permeability of free space, $e=$ electronic charge]

A
$\left(\frac{\mu_0 e v}{4 \pi B}\right)^{1 / 2}$
B
$\frac{\mu_0 e B}{4 \pi v}$
C
  $\frac{\mu_0 e V}{4 \pi B}$
D
$\left(\frac{\mu_0 e v}{B}\right)^{1 / 2}$
2
MHT CET 2020 16th October Evening Shift
MCQ (Single Correct Answer)
+1
-0

A circular coil of radius $$R$$ is carrying a current $$I_1$$ in anti-clockwise sense. A long straight wire is carrying current $$I_2$$ in the negative direction of $$X$$-axis. Both are placed in the same plane and the distance between centre of coil and straight wire is $$d$$. The magnetic field at the centre of coil will be zero for the value of $$d$$ equal to

A
$$\frac{R}{\pi}\left(\frac{l_2}{l_1}\right)$$
B
$$\frac{\pi}{R}\left(\frac{l_2}{l_1}\right)$$
C
$$\frac{\pi}{R}\left(\frac{l_1}{l_2}\right)$$
D
$$\frac{R}{\pi}\left(\frac{l_1}{l_2}\right)$$
3
MHT CET 2020 16th October Evening Shift
MCQ (Single Correct Answer)
+1
-0

An $$\alpha$$-particle of energy 10 eV is moving in a circular path in uniform magnetic field. The energy of proton moving in the same path and same magnetic field will be [mass of $$\alpha$$-particle $$=4$$ times mass of proton]

A
8 eV
B
16 eV
C
4 eV
D
10 eV
4
MHT CET 2020 16th October Morning Shift
MCQ (Single Correct Answer)
+1
-0

An electron $$(e)$$ is revolving in a circular orbit of radius $$r$$ in hydrogen atom. The angular momentum of the electron is ($$M=$$ magnetic dipole moment associated with it and $$m=$$ mass of electron)

A
$$\frac{m M}{e}$$
B
$$\frac{3 M m}{e}$$
C
$$\frac{2 m M}{e}$$
D
$$\frac{4 m M}{e}$$
MHT CET Subjects
EXAM MAP