Physics-
General
Easy
Question
A conducting loop carrying a current 
is placed in a uniform magnetic field pointing into the plane of the paper as shown. The loop will have a tendency to
- Contract
- Expand
- Move towards
- Move towards
The correct answer is: Expand
Net force on a current carrying loop in uniform magnetic field is zero. Hence the loop can’t translate. So, options [c] and [d] are wrong. From Fleming’s left hand rule we can see that if magnetic field is perpendicular to paper inwards and current in the loop is clockwise (as shown) the magnetic force 
on each element of the loop is radially outwards, or the loops will have a tendency to expand.
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