A bullet of mass 4.5 g is fired horizontally into a 2.7 kg wooden block at rest on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.31. The bullet comes to rest in the block, which moves 2.10 m. What is the speed of the block immediately after the bullet comes to rest within it, and at what speed is the bullet fired?

260 miles per hour

explanation:

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.