Answer:
The strength of magnetic field is 0.2 Tesla.
Explanation:
Data from the question is
Length (L) of wire ; L=0.10 m
Current in wire ; I= 2.0 A
Force on wire ; F = 0.04 N
Angle = Right angle So, 

Now ,
We have to find the magnetic Field strength (B)
For this formula for Force on wire in magnetic field is

Further modified as

Now insert values in the formula


So, the strength of magnetic field is 0.2 Tesla.