Answer:
The radius of the loop is 
Explanation:
Given that,
Current = 0.2kA = 200 A
Number of turns = 35
Magnetic field = 8.9 nT
We need to calculate the radius of one loop
Using formula of magnetic field


Where, I = current
N = number of turns
B = magnetic field
r = radius
Put the value into the formula



Hence, The radius of the loop is 
According to Newton's 2nd law of motion, F =ma = 80x5 = 400N.
Answer:
Explanation:
Young's modulus of elasticity Y = stress / strain
stress = force / cross sectional area
= weight of 15 kg / π r²
= 15 x 9.8 / 3.14 x ( .025 x 10⁻² )²
stress = 74.9 x 10⁷ N / m²
strain = Δ L / L , Δ L is change in length and L is original length
Putting the values
strain = .0168 / 2.7 =.006222
Young's modulus of elasticity Y = 74.9 x 10⁷ / .006222
= 120.88 x 10⁹ N / m² .