PHY 102 ELITES

Calculate the maximum amount of current flowing through a 5mH inductor, if it stores 50 joules of energy

• 50 A
• 100 A
• 141 A

• 200 A

The current flowing through the primary windings of a 200/1200 step-up transformer is 6mA. Determine the secondary side current.

• 0.5mA

• 2.1mA

• 1.0mA

• 6mA

A p-type semi-conductor is doped with a

• penta-valent atom

• tri-valent atom

• tetravalent atom

• mono-atomic element

The phase angle of a series R.L.C circuit is usually positive when

• The capacitive reactance is greater than the inductive reactance

• The inductive reactance is greater than the capacitive reactance

• The inductive reactance is equal to the capacitive reactance

• None of the above

A 5.08 x 10^-11 kg particle moved in an orbit perpendicular to a uniform magnetic field of 8.06wb/m². Take the charge of the particle to be 1.6 x 10^-19 and approximate radius of orbit as 80mm. Calculate its frequency of motion.

• 3.4nHz

• 4.0nHz

• 5.3kHz

• 4.1kHz

An R.L.C circuit at resonance has its inductive reactance as 205.7ohm. Determine the capacitive reactance, if the resonance frequency is 62Hz.

• 411.4ohms

• 102.85ohms

• 205.7ohms

• 12,753 ohms

An 8.0 x 10^-12 electrically charged particle moving at a speed of 50m/s is placed in a uniform magnetic field that is orthogonal to the angle of motion. Determine the magnitude of the magnetic field strength, if a force of 720N is experienced by the particle.

• 5.4GT

• 11GT

• 3.2GT

• 1.8GT

A conducting material whose resistance is 71.212 at 27°C has its resistance decreased to 20.152 when the temperature reaches 330k. calculate the coefficient of resistance in per kelvin.

• -0.127k-1

• 0.090k-¹

• -0.0033k

• 0.08-*

A cylindrical shape bar magnet produces a flux density of 1.12T through the cross-sectional area of the magnet as it radiates a flux of 197.3μwb all over its surface, Evaluate the diameter of the magnet.

• 15mm

• 1.49 m

• 149cm

• 0.15m

The total number of diodes required for the construction of a bridged full wave rectifier is

• one

• two

• three

• four