Kirchhoff's circuit laws are two equalities that deal with the current and potential difference (commonly known as voltage) in the lumped element model of electrical circuits. They were first described in 1845 by German physicist Gustav Kirchhoff. This generalized the work of Georg Ohm and preceded the work of Maxwell.
Answer:
a) 
b)
parallel to the earth surface.
- In this case according to the Fleming's left hand rule the direction of movement of bee must be in a direction parallel to the earth surface and perpendicular to the electric field at the same time.
Explanation:
Given:
mass of the bee, 
charge acquired by the bee, 
a.
Electrical field near the earth surface, 
Now the electric force on the bee:
we know:




The weight of the bee:



Therefore the ratio :


b.
The condition for the bee to hang is its weight must get balanced by the electric force acing equally in the opposite direction.
So,



parallel to the earth surface.
- In this case according to the Fleming's left hand rule the direction of movement of bee must be in a direction parallel to the earth surface and perpendicular to the electric field at the same time.
<u>Answer:</u>
The correct answer option is D. The distance between the planet and the Sun changes as the planet orbits the sun.
<u>Explanation:</u>
Kepler’s laws of planetary motion, derived by the German astronomer Johannes Kepler, are the laws of physics that describe the motions of the planets in the solar system.
According to the Kepler's first law of planetary motion: the path on which the planets orbit around the sun is elliptical in shape, with the center of the sun at one focus.
Therefore, the distance between the Sun and the planets vary as the planet orbit around the sun.
Answer:
The magnitude of magnetic field at given point =
×
T
Explanation:
Given :
Current passing through both wires = 5.0 A
Separation between both wires = 8.0 cm
We have to find magnetic field at a point which is 5 cm from any of wires.
From biot savert law,
We know the magnetic field due to long parallel wires.
⇒ 
Where
magnetic field due to long wires,
,
perpendicular distance from wire to given point
From any one wire
5 cm,
3 cm
so we write,
∴ 

![B =\frac{ 4\pi \times10^{-7} \times5}{2\pi } [\frac{1}{0.03} + \frac{1}{0.05} ]](https://tex.z-dn.net/?f=B%20%3D%5Cfrac%7B%204%5Cpi%20%5Ctimes10%5E%7B-7%7D%20%5Ctimes5%7D%7B2%5Cpi%20%7D%20%5B%5Cfrac%7B1%7D%7B0.03%7D%20%2B%20%5Cfrac%7B1%7D%7B0.05%7D%20%5D)

Therefore, the magnitude of magnetic field at given point = 