If the moon were twice as far from the earth as it is now, the gravitational force it
exerts on the earth would be

One-fourth of the original gravitational force.

Explanation:

The gravitational force between two objects of masses is given as:

Where,

Therefore, the gravitational force is inversely proportional to the square of the distance between the masses.

Now, if the distance is doubled, then the force has to be reduced by a factor of one by four or gravitational force will one-fourth of the original.

Let us verify it.

If , then new gravitational force is,

As seen above, new gravitational force is one-fourth of the original gravitational force between moon and Earth.

a person with a mass of 106kg has a weight of 1060n

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.