Lorentz force and Biot-Savart law - Revision

The magnetic field B-field produced by a moving charge is perpendicular to which of the following?

• The direction of motion of the charge only

• The line between the charge and point P only

• Both the direction of motion of the charge and the line between the charge and point P

• Neither the direction of motion of the charge nor the line between the charge and point P

What is the orientation of the magnetic field B-field generated by a current-carrying wire in relation to the direction of the current?

• Parallel to the direction of the current

• Perpendicular to the direction of the current only

• Both parallel and perpendicular to the direction of the current

• Neither parallel nor perpendicular to the direction of the current

The path described by the charged particle entering magnetic field with an angle other than 90 is

• Circular

• Helical

• It obeys inverse cube law.

• it is along the line joining the electron and point of observation.

In Biot – Savart law the direction of dB is always

• along r

• Along dl

• perpendicular to r

• Perpendicular to both dl and r

The magnetic Field near a current carrying conductor is given by

• Coulomb’s law

• Lenz law

• Biot savart law

• Kirchhoff’s law

According to Biot-Savart law, Magnetic field at a point due to current carrying element depends on distance r of a point from Current Element as

• B ∝ r

• B ∝ 1/r

• B ∝ r²

• B ∝ 1/r ²

tesla is the unit of

• magnetic field

• electric field

• electric potential

• electric current

What is the magnetic permeability of free space constant equal to, considering its significance in electromagnetic theory?

• 3.14 x 10^-7 teslas x meters / amps, correlating to the approximation of pi in its formula

• 2 pi x 10^-8 teslas x meters / amps, often mistaken due to its resemblance to the magnetic constant's formula

• 4 pi x 10^-7 teslas x meters / amps, a fundamental constant in electromagnetism

• 6.28 x 10^-7 teslas x meters / amps, representing twice the value of pi in its incorrect form

• 1.2566370614 x 10^-6 henries per meter, another form of expressing the magnetic constant accurately

What does the Biot-Savart Law help to determine in the context of electromagnetism?

• The electric field intensity surrounding a stationary charged particle

• The gravitational force acting between two point masses in vacuum

• The magnitude and direction of an infinitesimally small magnetic field due to a moving charge

• The instantaneous velocity of a charged particle under the influence of a magnetic field

• The potential difference across two points in an electric circuit