ELECTROMAGNETISM
2 marks · EasyA straight vertical wire has a current flowing upwards. A student wants to show the direction of the magnetic field around the wire using the right-hand grip rule.
Describe the position of the thumb and fingers of the right hand when using this rule.
State the direction of the magnetic field as viewed from above the wire.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) Thumb points in direction of current (up); fingers curl in direction of magnetic field.
(b) The magnetic field circles the wire in a clockwise direction as seen from above.
Common mistakes: Using left hand or Fleming's rule.
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · 1 mark for correct description of how to use the right hand: thumb for current, fingers for field.
B1 (b) · 1 mark · 1 mark for stating field is clockwise from above.
Worked solution
a) The thumb of the right hand points upwards (direction of the current), and fingers curl around the wire showing the direction of the field. b) From above, the field circles the wire in a clockwise direction.