Answer:
(a) 135 kV
(b) The charge chould be moved to infinity
Explanation:
(a)
The potential at a distance of <em>r</em> from a point charge, <em>Q</em>, is given by
![V = -\dfrac{kQ}{r}](https://tex.z-dn.net/?f=V%20%3D%20-%5Cdfrac%7BkQ%7D%7Br%7D)
where ![k = 9\times 10^9 \text{ F/m}](https://tex.z-dn.net/?f=k%20%3D%209%5Ctimes%2010%5E9%20%5Ctext%7B%20F%2Fm%7D)
Difference in potential between the points is
![kQ\left[-\dfrac{1}{0.2\text{ m}} -\left( -\dfrac{1}{0.1\text{ m}}\right)\right] = \dfrac{kQ}{0.2\text{ m}} = \dfrac{9\times10^9\text{ F/m}\times3\times10^{-6}\text{ C}}{0.2\text{ m}}](https://tex.z-dn.net/?f=kQ%5Cleft%5B-%5Cdfrac%7B1%7D%7B0.2%5Ctext%7B%20m%7D%7D%20-%5Cleft%28%20-%5Cdfrac%7B1%7D%7B0.1%5Ctext%7B%20m%7D%7D%5Cright%29%5Cright%5D%20%3D%20%5Cdfrac%7BkQ%7D%7B0.2%5Ctext%7B%20m%7D%7D%20%3D%20%5Cdfrac%7B9%5Ctimes10%5E9%5Ctext%7B%20F%2Fm%7D%5Ctimes3%5Ctimes10%5E%7B-6%7D%5Ctext%7B%20C%7D%7D%7B0.2%5Ctext%7B%20m%7D%7D)
![PD = 135\times 10^3\text{ V} = 135\text{ kV}](https://tex.z-dn.net/?f=PD%20%3D%20135%5Ctimes%2010%5E3%5Ctext%7B%20V%7D%20%3D%20135%5Ctext%7B%20kV%7D)
(b)
If this potential difference is increased by a factor of 2, then the new pd = 135 kV × 2 = 270 kV. Let the distance of the new location be <em>x</em>.
![270\times10^3 = kQ\left[-\dfrac{1}{x}-\left(-\dfrac{1}{0.1\text{ m}}\right)\right]](https://tex.z-dn.net/?f=270%5Ctimes10%5E3%20%3D%20kQ%5Cleft%5B-%5Cdfrac%7B1%7D%7Bx%7D-%5Cleft%28-%5Cdfrac%7B1%7D%7B0.1%5Ctext%7B%20m%7D%7D%5Cright%29%5Cright%5D)
![10 - \dfrac{1}{x} = \dfrac{270000}{9\times10^9\times3\times10^{-6}} = 10](https://tex.z-dn.net/?f=10%20-%20%5Cdfrac%7B1%7D%7Bx%7D%20%3D%20%5Cdfrac%7B270000%7D%7B9%5Ctimes10%5E9%5Ctimes3%5Ctimes10%5E%7B-6%7D%7D%20%3D%2010)
![\dfrac{1}{x} = 0](https://tex.z-dn.net/?f=%5Cdfrac%7B1%7D%7Bx%7D%20%3D%200)
![x = \infty](https://tex.z-dn.net/?f=x%20%3D%20%5Cinfty)
The charge chould be moved to infinity
The main activity that is involved in studying of physics is the study of natural laws. The study of physics has to do with many aspects of the universe. Physics majorly looks into the natural laws that operate in the universe and describe how they affect matter in relation to time.
Answer:
2271.16N/C upward
Explanation:
The diagram well illustrate all the forces acting on the mass. The weight is acting downward and the force is acting upward in other to balance the weight.since the question says it is motionless, then indeed the forces are balanced.
First we determine the downward weight using
![W=mg\\g=9.81m/s^{2}](https://tex.z-dn.net/?f=W%3Dmg%5C%5Cg%3D9.81m%2Fs%5E%7B2%7D)
Hence for a mass of 3.82g 0r 0.00382kg we have the weight to be
![W=0.00382kg*9.81m/s^{2}](https://tex.z-dn.net/?f=W%3D0.00382kg%2A9.81m%2Fs%5E%7B2%7D)
![W=0.0375N](https://tex.z-dn.net/?f=W%3D0.0375N)
To calculate the electric field,
![E=f/q\\E=0.0375/16.5*10^{-6} \\E=2271.16N/C](https://tex.z-dn.net/?f=E%3Df%2Fq%5C%5CE%3D0.0375%2F16.5%2A10%5E%7B-6%7D%20%5C%5CE%3D2271.16N%2FC)
Since the charge on the mass is negative, in order to generate upward force, there must be a like charge below it that is repelling it, Hebce we can conclude that the electric field lines are upward.
Hence the magnitude of the electric force is 2271.16N/C and the direction is upward
I think, I do think.. that it is D.
Wouldn't it be simple to divide 5 from 20, that would equal 4.
4 earthworms per square meter.
K.E = 1/2*m*v^2 = 1/2(500)(3)^2 = 2250 J
m*g*h = 500(9.8)(30) = 147000 J
2250 + 147000 = 149250