What is a solenoid? Draw the magnetic field lines for a solenoid and a bar magnet. Compare the two and state one similarity.

(N/A) solenoid is a coil of many circular turns of insulated copper wire wrapped closely in the shape of a cylinder.
The magnetic field lines for a solenoid and a bar magnet are shown in the provided image.
Comparison and Similarity:
$1$. Similarity: The pattern of magnetic field lines produced by a current-carrying solenoid is identical to that of a bar magnet. In both cases,the field lines emerge from the North pole and enter the South pole outside the magnet,and travel from South to North inside the magnet.
$2$. Comparison: $A$ solenoid acts as an electromagnet,meaning its magnetic field can be turned on or off by controlling the current,whereas a bar magnet is a permanent magnet with a constant magnetic field.