robphy said:The point of grabbing the wire with your right-hand is to indicate
the sense of the magnetic field...
Specifically, a given point in space,
the magnetic field due to a long straight wire is
pointing tangent to a circle through your point and centered at the wire.
Which way along the circle (clockwise or counterclockwise)?
The way your right hand grabs the wire (with thumb along the positive current) indicates which way.
(It doesn't matter how much you curl it... The point is that your right hand can only curl in one direction.)
pyroknife said:yeah but how much do you curl your finger? All the way?
The right hand rule is a convention used in physics and engineering to determine the direction of a vector in a three-dimensional coordinate system. It is also used to determine the direction of a magnetic field created by a current-carrying wire.
To use the right hand rule, extend your thumb, index finger, and middle finger perpendicular to each other. The index finger represents the direction of the first vector, the middle finger represents the direction of the second vector, and the thumb represents the direction of the resulting vector.
The most common cause of confusion with the right hand rule is the orientation of the hand. Some people may use their left hand instead of their right hand, which can lead to incorrect results. Another cause of confusion is not understanding the concept of vectors and how they relate to each other.
To avoid confusion with the right hand rule, it is important to consistently use your right hand and understand the concept of vectors. It may also be helpful to practice using the right hand rule with different scenarios to become more familiar with it.
Yes, there are alternative methods to the right hand rule, such as the left hand rule or using cross products. However, the right hand rule is the most commonly used convention and it is important for scientists and engineers to be familiar with it.