Explanation:
It is given that,
Length of wire, l = 0.53 m
Current, I = 0.2 A
(1.) Approximate formula:
We need to find the magnitude of the magnetic field made by the current at a location 2.0 cm from the wire, r = 2 cm = 0.02 m
The formula for magnetic field at some distance from the wire is given by :


B = 0.000002 T

(2) Exact formula:


B = 0.00000199 T
or
B = 0.000002 T
Hence, this is the required solution.
Two objects in physical contact with each other are in thermal equilibrium when they reach the same temperature and an exchange of heat energy no longer occurs.<span> According to HyperPhysics, the relation of thermal equilibrium follows the Zeroth Law of Thermodynamics, which states that “if two systems are at the same time in thermal equilibrium with a third system, they are in thermal equilibrium with each other.” </span>
Constructive interference in performance halls and the elimination of echoes are reasons why choir concerts better in performance halls than in gymnasiums.
<h3>What is constructive interference?</h3>
Constructive interference is a phenomenon which occurs when two waves travelling in same direction and which are in phase add up together to produce a wave of greater amplitude.
Constructive interference occurs in performance halls while destructive interference occurs in gymnasiums.
Also in performance halls, echoes are minimized due to the padded walls and the curtains while echoes which disturb choir concerts occur in gymnasiums.
Therefore, choir concerts better in performance halls than in gymnasiums because of constructive interference in performance halls and the elimination of echoes.
Learn more about constructive interference and echoes at: https://brainly.in/question/2378717
<span>Don't know what you mean by Earths Spheres. The Earth is a sphere -- singular. And it is made up of LOTS of matter</span>