A force F(x) = (−7.0x2 + 3.0x) N acts on a particle. How much work (in J) does the force do on the particle as it moves from x = 3.0 m to x = 5.0 m?
Picking a convenient reference point of the potential energy to be zero at x = 0, find the potential energy for this force. (Use the following as necessary: x. Assume U(x) is in joules and x is in meters. Do not include units in your answer.)

kepler used the data from tycho blahe (his mentor) to construct the laws of planetary motion.

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.