PART A)
Electrostatic potential at the position of origin is given by

here we have



now we have


Now work done to move another charge from infinite to origin is given by

here we will have

so there is no work required to move an electron from infinite to origin
PART B)
Initial potential energy of electron




Now we know



now by energy conservation we will have
So here initial total energy is sufficient high to reach the origin
PART C)
It will reach the origin
Great experiment ! Everybody should try it if they can get the equipment.
It demonstrates a lot of things that are very hard to explain in words.
I hope the students remembered to tilt the axis of the globe. If they didn't,
and instead kept it straight up and down, then each city had pretty much
the same amount of bulb-light all the way around, and there were no seasons.
If the axis of the globe was tilted, then City-D had the least variation in
seasons. City-D is only 2° from the equator, so the sun is more direct
there all year around than it is at any of the others.
Answer: C (impulse acting on the object)
The momentum is defined as it is the impulse acting on the force . Change in momentum is known as Impulse. Impulse is used to increase or decrease the momentum of object.
From Newtons II law
F = m. a
= m. v/t <em>since a = rate of change of velocity.</em>
<em> </em>F . t = m . v
F . t is known as impulse momentum
Answer:
parallel connection:Advandages: 1. Every unit that is connected in a parallel circuit gets equal amount of voltage.2. It becomes easy to connect or disconnect a new element without affecting the working of other elements.3. If any fault happened to the circuit, then also the current is able to pass through the circuit through different paths.Disadvantages: 1. It requires the use of lot of wires.2. We cannot increase or multiply the voltage in a parallel circuit.3. Parallel connection fails at the time when it is required to pass exactly same amount of current through the units.series connection:Advantages: 1. Series circuits do not overheat easily. This makes them very useful in the case of something that might be around a potentially flammable source, like dry plants or cloth.2. Series circuits are easy to learn and to make. Their simple design is easy to understand, and this means that it’s simple to conduct repairs .3. we can add more power devices, they have a higher output in terms of voltage .4. The current that flows in a series circuit has to flow through every component in the circuit. Therefore, all of the components in a series connection carry the same current.Disadvantages: 1.If one point breaks in the series circuit,the total circuit will break.2. As the number of components in a circuit increases ,greater will be the circuit resistance.