Need help with this question! the answer is wrong and I don't get it.

P = 200 [kW]

Explanation:

To solve this problem we must first find the acceleration developed, by means of the following kinematic equation.

where:

vf = final velocity =  20 [m/s]

vo = initial velocity = 0

t = time = 3 [s]

Through newton's second law, which tells us that the sum of forces is equal to the product of mass by acceleration.

F = m*a

F = 1500*6.66

F = 10000[N]

The power can be calculated by multiplying the speed by the force.

P = F * v

P = 10000*20

P = 200000 [W] = 200 [kW]

less than one you can't create energy

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.