BTEC Eng L3 Unit 1 Electrical theory symbols and units check

Which formula would you use for this question?

A charge of 3µC flows through an LED in 2ms. Calculate the current.​

What is Inductance, L measured in?

• Farads

• Henry's

• Ohm's

• Hertz

What is charge, Q or q, measured in?

• Capacitance

• Farads

• Coulomb's

• Amps

What is the symbol for current?

• V

• R

• L

• I

The number for permittivity of free space is a constant on the formula sheet?

• True

• False

Answer explanation

It's the symbol ε₀

Radians are equivalent to the angle subtended at the centre of a circle by an arc equal in length to the radius.

• True

• False

• What???

Answer explanation

True - Radians are just another measurement of an angle. It's worth memorising the standard values.

In Coulomb's Law the symbol "r" corresponds to the radius of the atom.

• True

• False

Answer explanation

False - the "r" is the distance between the two atoms.

The measurement of +1 on they y axis of the sine wave graph is called the ...

• amplitude

• period

• frequency

• peak to peak

The value of time for the total of a sine wave is called the ...

• amplitude

• frequency

• peak

• period

The symbol for reactance is

• X

• R

• Z

• L