Answer:
Magnetic field experienced = 4.5 × 10⁻⁴ T
Explanation:
The magnetic field around an infinite straight current-carrying wire at a distance r from the wire is given by
B = (μ₀I)/(2πr)
B = ?
I = 20 KA = 20000 A
r = 8.9 m
μ₀ = magnetic permeability = 1.257 × 10⁻⁶ T.m/A
B = (1.257 × 10⁻⁶ × 20000)/(2π×8.9) = 4.5 × 10⁻⁴ T
Energy that transfers through the medium
Power = Net Force x velocity
Net force = driving force - force of resistance
Driving force = mass x acceleration
Acceleration = (final velocity - initial velocity) / time
Acceleration = (18 - 0) / 12 = 1.5 m/s²
Driving force = 1.5 x 10³ x 1.5
= 2250 N
Net force = 2250 - 400
= 1850
Power = 1850 x 18
= 3.33 x 10⁴ Watts