Basic Electrical Engineering

A power transformer is required to provide an 18V output from a 230V supply. If a secondary current of 1.5A is required, calculate the primary current (assume 100% efficiency).

Tags

NGSS.HS-PS3-3

Calculate the resistance of a 0.6 mm diameter copper conductor having a length of 375m. The specific resistance of copper is 0.017µΩm @ 20°C.

Find, for the circuit below, the applied emf (E).

Tags

NGSS.HS-PS2-5

Find, for the circuit below, the power dissipated in resistor R1.

Show, on the diagram below, the magnetic field patterns around each of the current carrying conductors. Include the: i) polarity of the fields ii) direction of the force acting on the conductors.

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5

Explain briefly one method of reducing each of the following losses in a transformer core: i) Hysteresis losses. ii) Eddy current losses.

An inductor having 720 turns produces a flux of 65 mWb. If the current in the inductor is 1.05 A, calculate the inductance.

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5

For the illustration opposite: name the device.

For the illustration opposite: describe how you would determine the polarity of the device.

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5

For the illustration opposite: draw the BS EN 60617-3:1996 circuit symbol for the device, indicating the polarity.