Find the power an electric motor

In summary, the formula for finding the power an electric motor would need to have for a man to ride his bike up a hill without pedalling is Power = Force x Velocity / Time. To find time, you must first find the angle of the hill and the acceleration of the bike. Then, using the work equation, substitute velocity for distance and solve for power. Another way to approach this problem is to recognize that power is equal to force times distance divided by time, assuming constant force and velocity. This method may be simpler if the variables are constant enough to use an integral.
  • #1
Monsu
38
1
hi, i need just a formula to go ahead with this. I am given two masses, m1 of man, and m2 of his bike. he is going up a hill with slope (sqroot3/3) and velocity (v). Now I need to find the power an electric motor would need to have for the man to b able to ride his bike up without pedalling.
Power = energy / time, right? how can i find the time? pls help urgently! :uhh:
 
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  • #2
1) First, you must find the angle that the hill makes. Actually, you might be able to skip this step, but I couldn't and still logically produce the rest of the equation.

2) Secondly, find the acceleration on the bike.

3) Now you know the force (since you know the mass and acceleration), you can find the work involved in moving the bike any incremental distance.

4) To find the power, substitute velocity for distance in the work equation.

I believe this will provide you with the correct answer.
 
  • #3
I just thought of another way to look at this:

Assuming these variable are constant enough for an integral to be a multiple,

Work is force times distance.

Velocity is distance divided by time.

Power is work divided by time. Therefore Power is force times distance divided by time.

This type of thinking ONLY works because force and velocity are constant. Since they are, though, it works :tongue2:
 

1. How do I calculate the power of an electric motor?

The power of an electric motor can be calculated by multiplying the voltage (V) by the current (I) in amperes (A). The resulting value is the power in watts (W).

2. What is the formula for finding the power of an electric motor?

The formula for finding the power of an electric motor is P = V x I, where P is power in watts, V is voltage in volts, and I is current in amperes.

3. Can I use the same formula to find the power of any type of electric motor?

Yes, the formula P = V x I is applicable to all types of electric motors, including DC motors, AC motors, and brushless motors.

4. How does the power of an electric motor affect its performance?

The power of an electric motor directly affects its performance. A higher power motor will be able to produce more torque and work more efficiently, while a lower power motor will have less torque and may struggle to perform certain tasks.

5. Is there a relationship between power and speed in an electric motor?

Yes, there is a direct relationship between power and speed in an electric motor. As the power increases, the speed of the motor also increases. This can be seen in the motor's RPM (revolutions per minute) rating, which indicates how fast the motor can rotate under a specific amount of power.

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