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Answer:
2.24 T
Explanation:
From Electromagnetic Field,
F = BILsin∅................ Equation 1
Where F = Force on the wire, B = Field strength, I = current flowing in the conductor, L = length of the conductor, ∅ = The angle the conductor makes with the magnetic field.
Making B the subject of the equation,
B = F/ILsin∅..................... Equation 2
Given: F = 2.15 N, I = 32 A, L = 3.00 cm = 0.03 m, ∅ = 90° ( the wire is perpendicular to the magnetic field)
Substitute into equation 2
B = 2.15/(32×0.03×sin90°)
B = 2.15/0.96
B = 2.24 T.
Hence the Field strength = 2.24 T
Answer:
a)The approximate radius of the nucleus of this atom is 4.656 fermi.
b) The electrostatic force of repulsion between two protons on opposite sides of the diameter of the nucleus is 2.6527
Explanation:

= Constant for all nuclei
r = Radius of the nucleus
A = Number of nucleons
a) Given atomic number of an element = 25
Atomic mass or nucleon number = 52


The approximate radius of the nucleus of this atom is 4.656 fermi.
b) 
k=
= Coulombs constant
= charges kept at distance 'a' from each other
F = electrostatic force between charges


Force of repulsion between two protons on opposite sides of the diameter



The electrostatic force of repulsion between two protons on opposite sides of the diameter of the nucleus is 2.6527