A piling for a high-rise building is pushed by two bulldozers at exactly the same time. One bulldozer exerts a force of 1250 pounds in a westerly direction. The other bulldozer pushes the piling with a force of 2650 pounds in a northerly direction. What is the magnitude of the resultant force upon the piling, to the nearest ten pounds? a. 2340 lbs. c. 3900 lbs. b. 2670 lbs. d. 2930 lbs.]

(d) 2930 lbs

Explanation:

Given:

Force acting in the westerly direction is,

Force acting in the northerly direction is,

Now, as the two given directions are at right angles to each other, the angle between the two force vectors is 90 degrees.

So, when two vectors are at right angles, their resultant magnitude is given as:

Plug in the given values and solve for resultant 'R'. This gives,

Therefore, the magnitude of the resultant force upon the piling is 2930 lbs.

So, option (d) is correct.

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.

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