An inclined plane creates a mechanical advantage of 5. What would the input force need to be to create an output force of 20 N? A. 15 N
B. 100 N
C. 4 N

What is the most useful equation for electric power?

This is the number of complete movements of a wave per second.

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.