Question

A current carrying wire is kept along the axis of a circular loop carrying a current. The
straight wire,
a) Will exert an inward force on the circular loop.
b) Will exert an outward force on the circular loop.
c) Will exert a force on the circular loop parallel to itself.
d) Will not exert any force on the circular loop.​

Answer 1

Answer:

a) will exert an inward force on the circular loop

Answer 2

A current carrying wire is kept along the axis of a circular loop carrying a current. The  straight wire,will exert a force on the circular loop parallel to itself.

Explanation:

• A wire having the magnetic force carries the electric current i. The force is shown as $F \rightarrow=i .(l \rightarrow \times B \rightarrow \bar{F} \rightarrow=i .(l \rightarrow \times B \rightarrow)$, where B is the magnetic field and l is the length of the wire.
• If a straight wire carries the current and is kept along the circular loop that carries current, then the magnetic field that occurs on the current-carrying loop will be laterally on its circumference.
• This is according to the right-hand thumb rule. This also shows that it contains a current element$(l \rightarrow \times B \rightarrow)=0$.
• So, the cross product is $(l \rightarrow \times B \rightarrow)=0$

       $\Rightarrow F \rightarrow=0(l \rightarrow \times B \rightarrow)=0$

       $\Rightarrow F \rightarrow=0$

• So, it can be concluded that there will not be any force on the loop because of the straight wire.