The device used to magnetise a piece of magnetic material is called an electromagnet. The process of magnetising a cylinder made of soft iron involves using a solenoid (a coil of wire) through which current is passed.
In the diagram above: The soft iron cylinder is placed inside a solenoid. A current is passed through the solenoid, creating a magnetic field that magnetises the soft iron cylinder.
The direction of the magnetic field inside the solenoid is indicated by the arrows.
Three long straight wires carrying current are arranged mutually parallel as shown in the figure. The force experienced by \(15\) cm length of wire \(Q\) is ________. (\( \mu_0 = 4\pi \times 10^{-7}\,\text{T m A}^{-1} \)) 

Read the following sources of loan carefully and choose the correct option related to formal sources of credit:
(i) Commercial Bank
(ii) Landlords
(iii) Government
(iv) Money Lende