Total pressure is constant and PT = P = 1/2*ρ*v^2
So p1 + 1/2*ρ*v1^2 = p2 + 1/2*ρ*v2^2 and from continuity we have ρ*A1*v1 = ρ*A2*v2
So v2 = v1*A1/A2 since r2 = 2r1 then A2 = 4A1
so v2 = v1/4
Now from above p2 = p1 + 1/2*ρ*v1^2 - 1/2*ρ*v2^2 = p1 + 1/2*ρ*v1^2 - 1/2*ρ*v1^2/4^2
So p2 = 3.0x10^4Pa + 1/2*1000kg/m^3*(12m/s)^2 - 1/2*1000kg/m^3*12^2/16
= 9.75x10^4Pa = 9.8x10^4Pa
3 number of days are given form different activities of sales and purchase.
Day 2:
Earnings : $16
Spendings : $7.
Day 3:
Earnings : $22
Spendings : $12.
Please note: We always add the Earnings and Subtract the Spendings.
Therefore, the expression can be used to model the situation for these 2 days as
First day earning - First day spendings + Second day earning - Second day spendings
16-7 + 22 -12.
In order to write the expression as adding the additive inverse, we need to factor out minus from second group by making expression into two groups.
We will write two positive numbers in first group and two negative numbers in second group.
(16+22) + (-7-12).
Factoring out minus sign from second group, we get
(16+22) - (7+12)
This expression in additive inverse form now.
The answer is 83. First divide 10 by 2, which is 5 for a remaining 85-5+3. 85 - 5 is 80 and 80 + 3 is 83.
The second one is your answer
