Answer:
Current, I = 1000 A
Explanation:
It is given that,
Length of the copper wire, l = 7300 m
Resistance of copper line, R = 10 ohms
Magnetic field, B = 0.1 T

Resistivity, 
We need to find the current flowing the copper wire. Firstly, we need to find the radius of he power line using physical dimensions as :




r = 0.00199 m
or

The magnetic field on a current carrying wire is given by :



I = 1000 A
So, the current of 1000 A is flowing through the copper wire. Hence, this is the required solution.
Answer:
a.) F = 3515 N
b.) F = 140600 N
Explanation: given that the
Mass M = 74kg
Initial velocity U = 7.6 m/s
Time t = 0.16 s
Force F = change in momentum ÷ time
F = (74×7.6)/0.16
F = 3515 N
b.) If Logan had hit the concrete wall moving at the same speed, his momentum would have been reduced to zero in 0.0080 seconds
Change in momentum = 74×7.6 + 74×7.6
Change in momentum = 562.4 + 562.4 = 1124.8 kgm/s
F = 1124.8/0.0080 = 140600 N
Answer:
I = 69.3 μA
Explanation:
Current through the straight wire, I = 3.45 A
Number of turns, N = 5 turns
Diameter of the coil, D = 1.25 cm
Resistance of the coil, 
Distance of the wire from the center of the coil, d = 20 cm = 0.2 m
The magnetic field, B₁, when the wire is at a distance, d, from the center of the coil.

Magnetic field B₂ when the wire is at a distance, 2d from the center of the coil


Change in the magnetic field, ΔB = B₂ - B₁ = 0.00001725 - 0.0000345
ΔB = -0.000001725
Induced current, 
E = -N (Δ∅)/Δt
Δ∅ = A ΔB
Area, A = πr²
diameter, d = 0.0125 m
Radius, r = 0.00625 m
A = π* 0.00625²
A = 0.0001227 m²
Δ∅ = -0.000001725 * 0.0001227
Δ∅ = -211.6575 * 10⁻¹²
E = -N (Δ∅)/Δt

Resistance, R = 3.25 μ ohms = 3.25 * 10⁻⁶ ohms
I = E/R

I = 0.0000693 A
I = 69 .3 * 10⁻⁶A
I = 69.3 μA
Answer:
Time period of the motion will remain the same while the amplitude of the motion will change
Explanation:
As we know that time period of oscillation of spring block system is given as

now we know that
M = mass of the object
k = spring constant
So here we know that the time period is independent of the gravity
while the maximum displacement of the spring from its mean position will depends on the gravity as


so we can say that
Time period of the motion will remain the same while the amplitude of the motion will change
Answer:
a) battery-->electrical current-->copper wire rotor -->magnet--> mechanical energy
Explanation: