# The Naked Scientists Forum

### Author Topic: Quick Mechanics Question  (Read 2055 times)

#### Entity

• First timers
• Posts: 2
##### Quick Mechanics Question
« on: 02/01/2006 06:03:11 »
Let me first say hello to all as this is my first post.
I just have a quick quesiton about electric motors: When buying an electric motor for some arbitrary purpose, I noticed that their power is rated in HP units. How does that relate to the torque a given motor is capable of producing? Is it even possible to get a torque rating given only hp? Im leaning towards no. -Thanks

#### another_someone

• Guest
##### Re: Quick Mechanics Question
« Reply #1 on: 02/01/2006 09:52:31 »
quote:
Originally posted by Entity

Let me first say hello to all as this is my first post.
I just have a quick quesiton about electric motors: When buying an electric motor for some arbitrary purpose, I noticed that their power is rated in HP units. How does that relate to the torque a given motor is capable of producing? Is it even possible to get a torque rating given only hp? Im leaning towards no. -Thanks

If I recollect correctly, power is torque times speed, so without knowing the speed at which you are measuring the torque, you cannot derive the power (or visa versa).
« Last Edit: 02/01/2006 09:53:00 by another_someone »

#### Soul Surfer

• Neilep Level Member
• Posts: 3345
• keep banging the rocks together
##### Re: Quick Mechanics Question
« Reply #2 on: 10/01/2006 10:11:04 »
You need to look in more details at the specification.  Most motors should show a graph of the allowable range of speed and torque for the use of the electrical motor.  There are several different kinds of electric motor and the one you need depends on the application.  for example is it going to be lightly loaded initially and speed up to its working load like a fan or will it have to start with a poweful torque  like a car.

Also you should really have put this post under a more appropriate topic you will be more likely to get useful replies

Learn, create, test and tell
evolution rules in all things
God says so!
« Last Edit: 10/01/2006 10:12:44 by Soul Surfer »

#### The Naked Scientists Forum

##### Re: Quick Mechanics Question
« Reply #2 on: 10/01/2006 10:11:04 »