Flemings Left-Hand Rule
Flemings Left-Hand Rule
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FLEMING’S LEFT HAND RULE is used to work out the DIRECTION of the FORCE created by the MOTOR EFFECT.
To use FLEMING’S LEFT HAND RULE, you need to hold your LEFT HAND with your THUMB, FIRST FINGER, and SECOND FINGER all PERPENDICULAR to each other:
Keeping all three of these PERPENDICULAR, you need to first line up the FIRST and SECOND finger with the FIELD and CURRENT in a diagram.
Then whatever direction your THUMB points in, tells you the direction the FORCE acts in. This usually means the wire will MOVE in that direction.
Let’s look at an example:
To find the direction the FORCE acts in, you need to first use FLEMING’S LEFT HAND RULE, and ROTATE your hand so it lines up with the field in the diagram.
The field points to the RIGHT as field lines always point AWAY from NORTH POLES and TOWARDS SOUTH POLES.
Now you can line up your FIRST finger with the FIELD and your SECOND FINGER with the CURRENT which is coming OUT of the page in this diagram.
After lining these two up, you can see that the thumb points UPWARDS, which means the force acts UPWARDS.
FLEMING’S LEFT HAND RULE is used to work out the DIRECTION of the FORCE created by the MOTOR EFFECT.
To use FLEMING’S LEFT HAND RULE, you need to hold your LEFT HAND with your THUMB, FIRST FINGER, and SECOND FINGER all PERPENDICULAR to each other:
Keeping all three of these PERPENDICULAR, you need to first line up the FIRST and SECOND finger with the FIELD and CURRENT in a diagram.
Then whatever direction your THUMB points in, tells you the direction the FORCE acts in. This usually means the wire will MOVE in that direction.
Let’s look at an example:
To find the direction the FORCE acts in, you need to first use FLEMING’S LEFT HAND RULE, and ROTATE your hand so it lines up with the field in the diagram.
The field points to the RIGHT as field lines always point AWAY from NORTH POLES and TOWARDS SOUTH POLES.
Now you can line up your FIRST finger with the FIELD and your SECOND FINGER with the CURRENT which is coming OUT of the page in this diagram.
After lining these two up, you can see that the thumb points UPWARDS, which means the force acts UPWARDS.
