A current carrying loop of wire lies flat on a table top. When viewed from above, the current moves around the loop in a counter
clockwise sense. What is the direction of the magnetic field caused by this current, outside the loop? The magnetic field A) circles the loop in a clockwise direction.
B) points straight up.
C) points straight down.
D) points toward the east.
E) circles the loop in a counterclockwise direction.
As per the rule of Right hand thumb rule we know that magnetic field due to a closed loop is given by the direction of the thumb of right hand when our fingers of right hand is curled in the direction of current in the loop.
Here it is given that current is flowing in the loop in counter clockwise direction.
So here we will curl our fingers in counter clockwise direction so due our thumb will indicate perpendicular to the plane of the loop outwards or straight upwards.
Distance is path length covered by particle. When particle moves along half circle, it covers half the circumference therefore distance covered is (2×pi×r)/2 = pi× r. ... Hence displacement is equal to diameter or 2 times the radius of circle.