Agate in an irrigation canal is constructed in the form of a trapezoid 2 m wide at the bottom, 38 m wide at the top, and 2 m high. it is placed vertically in the canal so that the water just covers the gate. find the hydrostatic force on one side of the gate.
note that your answer should be in newtons, and use g = 9.8 m/s2.

Explanation:

Area of trapezoid =[(2 + 38) / 2 ] x 2 = 40 sq m .

Pressure at the centre of the trapezium

= h d g = 1 x 10³ x 9.8 N / m²  ( height of centre is 1 m )

= 9800 N /m²

Total force required = pressure at the centre x total area

9800 x 40 = 392 x 10³ N.

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.