How will the electrostatic force between two electric charges change if the first charge is doubled and the second charge is only one third of the original charge? A) 4/9
B) 2/3
C) 6 times
D) 2/9

B)

Explanation:

The electric force between charges can be determined by;

F =

Where: F is the force, k is the Coulomb's constant, is the value of the first charge, is the value of the second charge, r is the distance between the centers of the charges.

Let the original charge be represented by q, so that;

= 2q

=

So that,

F = x

  = 2q x x

  = x

  = x

F = x

The electric force between the given charges would change by .

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.