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
4.2x - 1.4y = 2.1
-1.4y = -4.2x + 2.1
y = (-4.2/-1.4)x + 2.1/-1.4
y = 3x - 1.5 <==
Answer:
20%
Step-by-step explanation:
To change a fraction to a percentage , multiply by 100%
× 100%
= 0.2 × 100%
= 20%