Answer:
16.63265306 Kg
Explanation:
This is a Newtons to weight conversion.
Fg = weight
Fg = N/9.8
Use the law of conservation of charge: charge is always conserved. Here the system is the two balls, then the total initial charge of the two balls is the same of the total final charge of the two balls, which is +3.9 uC + 16.4 uC = +20.3uC.
When the balls are in contact, they behave as one alone piece and the total charge is evenly distributed among the whole surface. Given that the two balls are identical (same shape and same size) every ball support half of the charge.
Then, when the two balls are separated again each will have (+20.3 / 2) uC = 10.15 uC
To solve this problem, it is necessary to use the concepts related to the Force given in Newton's second law as well as the use of the kinematic equations of movement description. For this case I specifically use the acceleration as a function of speed and time.
Finally, we will describe the calculation of stress, as the Force produced on unit area.
By definition we know that the Force can be expressed as
F= ma
Where,
m= mass
a = Acceleration
The acceleration described as a function of speed is given by
Where,
Change in velocity
Change in time
The expression to find the stress can be defined as
Where,
F = Force
A = Cross-sectional Area
Our values are given as
Replacing at the values we have that the acceleration is
Therefore the force expected is
Finally the stress would be
Therefore the compressional stress that the arm withstands during the crash is 49.97Mpa