Monochromatic light with lambda equals 630 space n m is incident on a single slit. The slit width is 0.8 mm. If the distance between the screen and slit is 1.8 m, what is the width of the central bright fringe on the screen

The angular width is "" and the linear width is "".

Explanation:

Given:

Wavelength,

or,

Slit width,

or,

Distance between slit and screen,

As we know,

The central bright fringe's angular height,

⇒

and,

The linear width will be:

⇒

By substituting the values, we get

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.