Physics Exam Quiz

Coulomb

90 degrees

Resistivity increases with temperature due to increased electron collisions.

Connect a high resistance in parallel with the galvanometer.

North-South

1/2 * L * I^2

Opposite to the current in the loop.

Same direction as the current in the loop.

An ideal step-up transformer decreases current to increase voltage, maintaining constant power.

Displacement current is due to a changing electric field.

Forms a virtual, enlarged image.

Intensity of emergent light = I₀ * cos²θ.

Emission of electrons from a heated metal surface.

Most go undeviated because most of the atom is empty space.

Called isotopes.

Conductors have energy band gaps <3 eV; insulators have energy band gaps > 3 eV; semiconductors have energy band gaps between 0 and 3 eV.

A molecule with a permanent dipole moment due to uneven charge distribution.

Always zero, a fundamental law of magnetism.

A rotating vector representing alternating quantities.

A surface of constant phase in a wave.

Packet of light energy that behaves as a particle in interactions with matter.

The net electric flux through any closed surface is proportional to the enclosed charge.

Average velocity of electrons in a conductor due to an electric field.

Measure of how easily charge carriers move in a material.

Based on electromagnetic induction, converting mechanical energy to electrical energy.

Alternating due to reversing direction of induced emf/current.

The electric field at a point on the axis of an electric dipole is given by E = (1/4πε₀) * [2p cosθ / r³].

Effective emf of series combination is the sum of individual emfs; effective internal resistance is the sum of individual internal resistances.

Magnetic field at a point on the axis of a circular current loop is given by B = (μ₀ / 4π) * (2π I R² / (z² + R²)^(3/2))

Constructive interference occurs when the phase difference between waves is 2nπ, where n is an integer.

Destructive interference occurs when the phase difference between waves is (2n + 1)π, where n is an integer.

A rectifier converts AC to DC current; a full-wave rectifier uses diodes to achieve this over 360 degrees.

Potential at a point due to a charge q is given by V=kq/r, where k is the Coulomb constant

The work done in moving a charge q from infinity to point P is W=qV(P), where V(P) is the potential at P. Path independence.

In a series AC circuit with an inductor, capacitor, and resistor, the current may lead or lag the voltage depending on the frequency and component values.

The angle of minimum deviation is the angle of incidence and refraction that results in the smallest deviation in light passing through the prism.