Answer:
The charge density in the system is 
Explanation:
To solve this problem it is necessary to keep in mind the concepts related to current and voltage through the density of electrons in a given area, considering their respective charge.
Our data given correspond to:

We need to asume here the number of free electrons in a copper conductor, at which is generally of 
The equation to find the current is

Where
I =Current
V=Velocity
A = Cross-Section Area
e= Charge for a electron
n= Number of free electrons
Then replacing,


Now to find the linear charge density, we know that

Where:
I: current intensity
Q: total electric charges
t: time in which electrical charges circulate through the conductor
And also that the velocity is given in proportion with length and time,

The charge density is defined as

Replacing our values


Therefore the charge density in the system is 
Answer:
40000 N
Explanation:
Force: This cam be defined as the product of mass and acceleration.
From the question,
The braking force of the lorry will be the same in magnitude as the force at which the lorry is moving.
F = ma..................... Equation 1
Where m = mass of the lorry, a = acceleration/deceleration of the lorry.
Given: m = 5000 kg, a = 8 m/s²
Substitute these values into equation 1
F = 5000(8)
F = 40000 N
Explanation:
The logarithmic damping decrement of a mathematical pendulum is DeltaT=0.5. How will the amplitude of oscillations decrease during one full oscillation of the pendulum
Answer:
The helium contained in the Sun's atmosphere was produced by fusion of hydrogen to helium in the Sun's core. Since planets including the sun where all formed at the same time, Jupiter's atmosphere also contains Helium.
Explanation:
1) the helium in the suns atmosphere from the original helium and any helium the sun has produced from the nuclear fusion of hydrogen.
2) the helium present in Jupiter's atmosphere came from the helium in the matter that produced our solar system.
3) the helium found in the suns core comes only from the nuclear fusion of hydrogen