A uniform electric field exists everywhere in the x, y plane. The electric field has a magnitude of 3500 N/coil, and is directed in the positive x direction. A point charge of -9.0 x 10-9 coil is placed at the origin. Determine the magnitude of the net electric field at: (a) x

5525 N/C

Explanation:

Magnitude of electric field ( E ) = 3500 N/c

Direction of electric field : positive X axis

point charge ( q ) = -9.0 * 10^-9

Calculate the Magnitude of the net electric field  at (a) x = -0.20 m

Magnitude =  5525 N/C

Electric field due to q = ( 9 * 10^9 * 9 * 10^-9 ) / ( -0.2 )^2  

                                    = 81 / 0.04 = 2025 N/c

Therefore the magnitude of the net electric field

= 2025 + 3500

= 5525 N/C

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.