Kelvin temperature is -80K. What is the corresponding temperature on celsius scale?

If an electric circuit is not grounded it is best to reach out and touch it to provide the ground a.true or b.false

Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.

Diverging mirrors and lenses always produce images