A car traveling at 10 m/s starts to decelerate steadily. It comes to a complete stop in 20 seconds. What is the acceleration?

Explanation:

Your initial velocity () is 10 m/s, your time is 20 seconds. Although it is not explicitly mentioned in the problem, since you know the car comes to a stop, your final velocity () is 0 m/s.

The equation you can use to solve for acceleration (a) is

1. Plug in the numbers you do have, so your equation will look like this:

0=10+a(20)

2. Solve for a.

-10= 20a

-10/20=a

-0.5= a

a = -0.5

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.