Speed is the measure of how far something travels in a given period of time. It is also known as the rate of change in position.
For a Motor , Speed is measured in revolutions per minute (RPM ).
Torque is force exerted as an object rotates.To turn , a motor shaft requires certain amount of torque.
If some load is added to the shaft , more torque is required to turn it.
Two motors of different sizes may run at the same speed.
A Shaded pole motor ( example ;- window fan ) exerts very little torque.Its common speed is 1200 to 1800 RPM.
Whereas a large Industrial motor (example ;- factory conveyor belt ) may exert a very high torque in order to start a heavy load , and yet it turns at a similar speed.
The same is true for engines. An Eight cylinder car engine can run at 3600 RPM and exert a great amount of torque.
A small generator will run at 3600 RPM , but not exert nearly as much torque as the car.