You find net charge by subtracting the number of electrons from the number of protons (since protons are positive and electrons are negative). 9 - 10 = -1
Back emf is 85.9 V.
<u>Explanation:</u>
Given-
Resistance, R = 3.75Ω
Current, I = 9.1 A
Supply Voltage, V = 120 V
Back emf = ?
Assumption - There is no effects of inductance.
A motor will have a back emf that opposes the supply voltage, as the motor speeds up the back emf increases and has the effect that the difference between the supply voltage and the back emf is what causes the current to flow through the armature resistance.
So if 9.1 A flows through the resistance of 3.75Ω then by Ohms law,
The voltage across the resistance would be
v = I x R
= 9.1 x 3.75
= 34.125 volts
We know,
supply voltage = back emf + voltage across the resistance
By plugging in the values,
120 V = back emf + 34.125 V
Back emf = 120 - 34.125
= 85.9 Volts
Therefore, back emf is 85.9 V.
To determine the amplitude of a wave, you would need to know the : B. Maximum displacement of the wave from the equilibrium position
You can find out the displacement by counting the waves that is
written on the Graph
Hope this helps
Potential energy to kinetic energy
The answer is Metal I'm 100% positive