Answer:
The electric field at x = 3L is 166.67 N/C
Solution:
As per the question:
The uniform line charge density on the x-axis for x, 0< x< L is
Total charge, Q = 7 nC =
At x = 2L,
Electric field,
Coulomb constant, K =
Now, we know that:
Also the line charge density:
Thus
Q =
Now, for small element:
Integrating both the sides from x = L to x = 2L
Similarly,
For the field in between the range 2L< x < 3L:
Now,
If at x = 2L,
Then at x = 3L:
Answer:
1. The bird close to the center
2. 4/25 of the original force.
Explanation:
1. Tangential velocity is v=w*d (in m/s), where w is the rotational speed, commonly denoted as the letter omega (in radians per second). d is the distance from the center of the rotating object to the position of where you would like to calculate the velocity (in meters).
As we can note, the furthest from the center we are calculating the velovity the higher it is, because the rotational velocity is not changing but the distance of the object with respect to the center is. If v=w*d, then the lower the d (distance) the lower the tangential velocity.
2. Take a look at the picture:
We have the basic equation for the gravitational force.
We have to forces: Fg1, which is the original force, and Fg2, the force when the mass and the distance changes.
If we consider that mass 2 didn't change (m2'=m2), mass 1 is four times its original (m1'=4*m1) and distance is 5 times the original (r'=5*r), then next step is just plugging it into the equation for Fg2.
Dividing the original force Fg1 by the new force Fg2 (notice you can just as well do the inverse, Fg2 divided by Fg1) gives us the relation between the forces, cancelling all the variables and being left only with a simple fraction!
