left hand and right hand rule???

Watch
This discussion is closed.
planecrazy
Badges: 0
#1
Report Thread starter 15 years ago
#1
when do you use the left hand rule and when do you use the right hand rule? my teacher said you use the left for when doing a motor but what would you class as a motor?
0
jaffakidds
Badges: 0
#2
Report 15 years ago
#2
generally use right hand for direction of induced emf's (Lenz's Law)
0
selkie222
Badges: 2
Rep:
?
#3
Report 15 years ago
#3
I gave up physics since AS and am operating on GCSE level knowledge, so ignore me if I make no sense...

left hand rule is used to find force
right hand rule is used to find current (I)

I'll go away now and back to chemistry (much safer territory for me!)

selkie
0
elpaw
Badges: 15
Rep:
?
#4
Report 15 years ago
#4
use the left hand rule with motors, and the right hand rule with dynamos.

motors are machines that change electromagnetic energy into kinetic energy, i.e. currents and voltages into motion; dynamos are machines that change kinetic energy into electromagnetic energy, i.e. motion into voltages and currents.
0
crana
Badges:
#5
Report 15 years ago
#5
this is basically what others have said, but here are my revision notes on hand rules:

HAND RULES

first finger field
second finger current
thumb motion

Fleming’s Left Hand Rule
Used when a current from an external source flows through a conductor in a magnetic field, resulting in a force.

e.g. motor
motors drive cars and we drive on the left

Fleming’s Right Hand Rule
Used when an external force produces a motion on a conductor in a magnetic field, inducing a current to flow in the conductor.

e.g. generator/dynamo

Other Right Hand Rule
Point thumb in direction of current; fingers show direction of magnetic field.

You get a “thumbs up” when you are right!
0
X
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

If you do not get the A-level grades you want this summer, what is your likely next step?

Take autumn exams (50)
42.74%
Take exams next summer (23)
19.66%
Change uni choice through clearing (29)
24.79%
Apply to uni next year instead (12)
10.26%
I'm not applying to university (3)
2.56%

Watched Threads

View All