Find resistance and current.?

Question

I need to find the resistance and current and only have the voltage. Thew voltage is 240, the motor is 4kW the power consumed is 3522.105W. torque of the motor is 103.5nm and it is moving at 34.03 rad/s or 3.91 m/s I need to find the resistance and current any help or equations will be greatly appreciated! cheers

Answer 1

The link between voltage, current and resistance (Ohm's Law)
If you know two of these, you can work out the last one using this formula:

V = I x R

V = The voltage across a component

I = The current going through a component

R = The resistance of a component

The other ways of writing Ohm's Law are:

R = V/I or I = V/R

The symbol for voltage is V. It is measured in units of Volts V

The symbol for current is I. It is measured in units of Amps A

The symbol for resistance is R. It is measured in units of Ohms

Answer 2

If the effects of inductance and power factor are ignored, the power = V x I where V is the voltage and I the current. But the data given suggests that a 4kW motor is consuming 3522 W indicating a power factor of nearly 0.9 which is not abnormal.

In this situation, we need to do more detailed calcualtions to get the Resistance and the current. Right now, I lack access to the books that deal with this.

Answer 3

The current is the consumed power divided by the voltage. The dynamic resistance is the voltage divided by the current.

Answer 4

Power (W) = Voltage (V) x Current (A)
so Amps (current) = W/V
A = 3522.105/240 = 14.675A
(rated power was) 4000/240 = 16.667A (rated current)

Voltage = Current x Resistance
So Resistance = V/A
R = 240 / 14.675 = 16.35 Ohms

Answer 5

Power=currentXvoltage
Rated current=4000/240 consumed current=3522.105/240
Power=voltageXvoltage/resistance
rated resistance=240X240/4000
Effective instantaneous resistance=240X240/3522.105

Answer 6

P= Vexp(2)/R => R= Vexp(2)/ P = 240exp(2)/4k = 57600/4k =14.4 ohms
effective current I= V/R = P/V =4k/240 = 16.666~ A