Motor oil, with a viscosity of 0.25 n ∙ s/m2, is flowing through a tube that has a radius of 3.0 mm and is 1.0 m long. the drop in pressure over the length of the tube is 200 kpa. what is the average speed of the oil

The average speed of the oil is 1 m/s.

Explanation:

Given that,

Viscosity

Radius r = 3.0 mm

Length = 1.0 m

Pressure = 200 kPa

We need to calculate the average speed of the oil

Using formula of pressure

Where, A = area

= density of oil

= viscosity

Put the value into the formula

Hence, The average speed of the oil is 1 m/s.

d.7.5cm is your answer

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.