Φ = 6.28 mWb.
The magnetic flux, it is a measure of the amount of magnetism, and it is calculated from the magnetic field, the surface on which it acts and the angle of incidence formed between the magnetic field lines and the different elements of said surface.
The magnetic flux unit in the International System of Units is the weber and is designated by Wb (which is why we know how webermeters are the devices used to measure the magnetic flux) given by the equation Φ = BAcosθ, where B is the magnetic field and A is the area of the surface in the magnetic field.
To solve this exercise we have to find the area of the circular loop:
A = πr² = π(0.10m)²
Due the plane of the loop and the magnetic field vector are parallel θ = 0°. So:
Φ = BAcosθ
With B = 0.20T and A = π(0.10m)²
Φ = (0.20T)[π(0.10m)²]cos 0° = 0.00628 T m² = 0.00628 Wb = 6.28 mWb
