The direction of the force on the conductor when the direction of magnetic field and current are given was found to be opposite to the actual direction of the force on the conductor.
Consider the given reasons why the wrong direction was obtained and choose the correct answers:
Statement 1: The middle finger is taken as the direction of force and the thumb is taken as the direction of the current.
Statement 2: The right hand is used instead of the left hand.
The direction of the force on the conductor when the direction of magnetic field and current are given was found to be opposite to the actual direction of the force on the conductor.
Consider the given reasons why the wrong direction was obtained and choose the correct answers:
Statement 1: The middle finger is taken as the direction of force and the thumb is taken as the direction of the current.
Statement 2: The right hand is used instead of the left hand.
The correct option is A Either statement 1 or statement 2 could be the reason individually
In Fleming’s left-hand rule, if the forefinger represents the direction of magnetic field, the middle finger represents the direction of the current, then the thumb represents the direction of force if the fingers are stretched perpendicular to each other, as shown.
Now, if the middle finger is taken as the direction of force experienced by the conductor, and the thumb is taken as the direction of the current, we have:
If this is taken as the convention, then the wrist has to be rotated so that the forefinger is still pointing in the direction of magnetic field and the thumb points towards the direction of the current, the direction of force will be as shown below.
Here, the force direction will point into the plane of the paper, or in other words, away from you. But the actual direction of the force is out of the plane of the paper, which is towards you.
Now if the right hand is considered instead of the left, the thumb will point into the plane of paper when the other fingers are pointing in the respective directions. Hence, that can also be the mistake.
Now, in right hand, if the middle finger is taken as the direction of force, and the thumb is taken as the direction of the current, then the direction of force will be in accordance with the actual direction of the force. Hence those two errors individually will lead to the wrong direction of force, but collectively, in this case, will give the right direction for the force.
Either statement 1 or statement 2 could be the reason individually
In Fleming’s left-hand rule, if the forefinger represents the direction of magnetic field, the middle finger represents the direction of the current, then the thumb represents the direction of force if the fingers are stretched perpendicular to each other, as shown.
Now, if the middle finger is taken as the direction of force experienced by the conductor, and the thumb is taken as the direction of the current, we have:
If this is taken as the convention, then the wrist has to be rotated so that the forefinger is still pointing in the direction of magnetic field and the thumb points towards the direction of the current, the direction of force will be as shown below.
Here, the force direction will point into the plane of the paper, or in other words, away from you. But the actual direction of the force is out of the plane of the paper, which is towards you.
Now if the right hand is considered instead of the left, the thumb will point into the plane of paper when the other fingers are pointing in the respective directions. Hence, that can also be the mistake.
Now, in right hand, if the middle finger is taken as the direction of force, and the thumb is taken as the direction of the current, then the direction of force will be in accordance with the actual direction of the force. Hence those two errors individually will lead to the wrong direction of force, but collectively, in this case, will give the right direction for the force.
