- #1
Totter
- 8
- 0
An electric motor drives an electric generator.The 2hp motor draws 15A from a 120V D.C source and the generator supplies 5A to a 48Ohm LOAD. It is given that 1hp= 745.7W
Calculate the motor efficiency.
Calculate the generator efficiency.
Calculate overall efficiency.
Ok soo I went forward and did this.
Since 1hp = 745.7Watt I assumed that the motor would be going at 2x745.7W = 1491.4W .
So if you take the P = I.V and you insert 15A.120V = 1800W
So using n = Po/Pin for Efficiency 1491.4/1800 *100 = 82.85% efficiency.
Not sure if this is correct but now?
I can say P = I^2 / R and get the Watt but to what comparison? Which Po and which Pin ??
Please help
Calculate the motor efficiency.
Calculate the generator efficiency.
Calculate overall efficiency.
Ok soo I went forward and did this.
Since 1hp = 745.7Watt I assumed that the motor would be going at 2x745.7W = 1491.4W .
So if you take the P = I.V and you insert 15A.120V = 1800W
So using n = Po/Pin for Efficiency 1491.4/1800 *100 = 82.85% efficiency.
Not sure if this is correct but now?
I can say P = I^2 / R and get the Watt but to what comparison? Which Po and which Pin ??
Please help