# Moving Charges and Magnetism · Physics · COMEDK

Start Practice## MCQ (Single Correct Answer)

COMEDK 2024 Evening Shift

A current I flows in an infinitely long wire with cross section in the form of semi-circular ring of radius $$1 \mathrm{~m}$$. The magnitude of the ma...

COMEDK 2024 Evening Shift

A negative charge particle is moving upward in a magnetic field which is towards north. The particle is deflected towards

COMEDK 2024 Evening Shift

A wire of length $$2 \mathrm{~m}$$ carries a current of $$1 \mathrm{~A}$$ along the $$\mathrm{x}$$ axis. A magnetic field $$B=B_0(i+j+k)$$ tesla exist...

COMEDK 2024 Morning Shift

Current flows through uniform, square frames as shown in the figure.
In which case is the magnetic field at the centre of the frame not zero?
...

COMEDK 2024 Morning Shift

Two similar coils $A$ and $B$ of radius '$$r$$' and number of turns '$$N$$' each are placed concentrically with their planes perpendicular to each oth...

COMEDK 2024 Morning Shift

A circular coil of radius $$0.1 \mathrm{~m}$$ is placed in the $$\mathrm{X}-\mathrm{Y}$$ plane and a current $$2 \mathrm{~A}$$ is passed through the c...

COMEDK 2024 Morning Shift

Two circular coils of radius '$$a$$' and '$$2 a$$' are placed coaxially at a distance ' $$x$$ and '$$2 x$$' respectively from the origin along the $$\...

COMEDK 2023 Morning Shift

Two very long straight parallel wires carry currents $$i$$ and $$2 i$$ in opposite directions. The distance between the wires is $$r$$. At a certain i...

COMEDK 2023 Morning Shift

A straight wire of length $$2 \mathrm{~m}$$ carries a current of $$10 \mathrm{~A}$$. If this wire is placed in uniform magnetic field of $$0.15 \mathr...

COMEDK 2023 Morning Shift

A square wire of each side l carries a current $$I$$. The magnetic field at the mid-point of the square
...

COMEDK 2023 Evening Shift

A magnetic field does not interact with:

COMEDK 2023 Evening Shift

A metallic rod of $$10 \mathrm{~cm}$$ is rotated with a frequency 100 revolution per second about an axis perpendicular to its length and passing thro...

COMEDK 2023 Evening Shift

The radius of the current carrying circular coil is doubled keeping the current passing through it the same. Then the ratio of the magnetic field prod...

COMEDK 2023 Evening Shift

A circular loop of area $$0.04 \mathrm{~m}^2$$ carrying a current of $$10 \mathrm{~A}$$ is held with its plane perpendicular to a magnetic field induc...

COMEDK 2022

An electric current $I$ enters and leaves a uniform circular wire of radius $r$ through diametrically opposite points. A charged particle $$q$$ moves ...

COMEDK 2022

A regular hexagon of side $$m$$ which is a wire of length 24 m is coiled on that hexagon. If current in hexagon is $$I$$, then the magnetic moment,
...

COMEDK 2021

Two particles of masses $$m_1=m,m_2=2m$$ and charges $$q_1=q,q_2=2q$$ entered into uniform magnetic field. Find $$F_1/F_2$$ (force ratio).

COMEDK 2021

A long solenoid has 20 turns cm$$^{-1}$$. The current necessary to produce a magnetic field of 20 mT inside the solenoid is approximately

COMEDK 2021

A constant current flows from A to B as shown in the figure. What is the direction of current in the circle?
...

COMEDK 2020

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\wideh...

COMEDK 2020

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...

COMEDK 2020

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 sensitiv...

COMEDK 2020

The particle that cannot be accelerated by a cyclotron is