A bicyclist is traveling at +25 m/s when he begins to decelerate at -4 m/s2. How fast is he traveling after 5 seconds?

The bicyclist goes at 5 m/s

Explanation:

Motion With Constant Acceleration

It's a type of motion in which the velocity of an object changes uniformly in time.

The equation that rules the change of velocities is:

Where:

a   = acceleration

vo = initial speed

vf  = final speed

t    = time

It's given a bicyclist is traveling at v0=+25 m/s and decelerates at . We are required to calculate the speed after t=5 seconds.

Applying the formula:

The bicyclist goes at 5 m/s

this is poiselle's equation from fluid mechanic in physics. mech eng

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.