Answer:
C) No work is required to move the negative charge from point A to point B.
Explanation:
An equipotential surface is defined as a surface connecting all the points at the same potential.
Therefore, when a charge moves along an equipotential surface, it moves between points at same potential.
The work done when moving a charge is given by

where
q is the charge
is the potential difference between the initial and final point of motion of the charge
However, the charge in this problem moves along an equipotential surface: this means that the potential does not change, so

And so, the work done is also zero.
Substract two consecutive terms of the sequence to see if there is a common difference:

As we can see, there is a common difference of -6.
Then, if a number of the sequence is given, the next one can be found by adding -6 (which is the same as subtracting 6).
Notice that the first term of the sequence is 3.
Then, the rule for the sequence is to start with 3 and add -6 repeatedly.
Therefore, the correct choice is option A) Start with 3 and add -6 repeatedly.
Answer: Approximately 65% from what i have learnt.
Answer:We have , a relation in frequency f and wavelength λ of a wave having the velocity v as ,
v=fλ ,
given f=60Hz , λ=20m ,
therefore velocity of wave , v=60×20=1200m/s