Answer:

Explanation:
It says “Momentum before the collision is equal to momentum after the collision.” Elastic Collision formula is applied to calculate the mass or velocity of the elastic bodies.












Your heart rate is higher than normal.
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:
B = 4.059 x 10¹⁵ T
Explanation:
Given,
Number of loop, N = 400
radius of loop, r = 0.65 x 10⁻¹⁵ m
Current, I = 1.05 x 10⁴ A
Magnetic field at the center of the loop


B = 4.059 x 10¹⁵ T