A heavy paddle moving with velocity v hits a light ball moving in the opposite direction with velocity 3v. Assuming that the collision is perfectly elastic, what is the final speed of the ball? (Note that the paddle is much more massive that the ball and think about what the collision looks like in the reference frame of the paddle).

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.

the answer is b, have negligible mass

because growing process had stoped after 4-5 year