Bohr is the scientist you are looking for my friend...;)
Answer:
The woman's distance from the right end is 1.6m = (8-6.4)m.
The principles of moments about a point or axis running through a point and summation of forces have been used to calculate the required variable.
Principle of moments: the sun of clockwise moments must be equal to the sun of anticlockwise moments.
Also the sun of upward forces must be equal to the sun of downward forces.
Theses are the conditions for static equilibrium.
Explanation:
The step by step solution can be found in the attachment below.
Thank you for reading this solution and I hope it is helpful to you.
Answer 1) The electric field at distance r from the thread is radial and has magnitude
E = λ / (2 π ε° r)
The electric field from the point charge usually is observed to follow coulomb's law:
E = Q / (4 π ε°
)
Now, adding the two field vectors:
= {2.5 / (22 π ε° X 0.07 ) ; 0}
Answer 2)
= {2.3 / (4 2 π ε°) ( - 7/ (√(84); -12 / (√84))
Adding these two vectors will give the length which is magnitude of the combined field.
The y-component / x-component gives the tangent of the angle with the positive x-axes.
Please refer the graph and the attachment for better understanding.
D is the best answer. In many physics problems we treat an extended object as if it were a point with the same mass located at the center of mass.