Question

1. a fluid flows through a pipe that narrows. describe how the speed and pressure of the fluid change in the narrow section.
2. give a real - world example where bernoullis principle is observed (other than airplane wings).
3. convert 5000 milligrams to kilograms.
4. why is speed considered as a scalar quantity and velocity as a vector quantity?
5. 350 miles/hr ne. is it scalar or vector?

Explanation:

Step1: Apply continuity equation

According to the continuity equation $A_1v_1 = A_2v_2$ (where $A$ is cross - sectional area and $v$ is velocity). As the pipe narrows ($A_2

Step2: Apply Bernoulli's principle

Bernoulli's principle for horizontal flow is $P_1+\frac{1}{2}
ho v_1^2=P_2+\frac{1}{2}
ho v_2^2$. Since $v_2 > v_1$, the pressure $P_2$ in the narrow section is lower than $P_1$.

A real - world example of Bernoulli's principle is the flow of air over a chimney. The air moving over the top of the chimney has a higher speed than the air inside the chimney. According to Bernoulli's principle, the pressure above the chimney is lower than the pressure inside the chimney, which helps in drawing the smoke out of the chimney.

Step1: Use conversion factors

We know that $1$ kilogram ($kg$)=$1000$ grams ($g$) and $1$ gram ($g$) = $1000$ milligrams ($mg$). So, $1$ kg=$1000\times1000$ mg = $10^6$ mg.

Step2: Perform the conversion

To convert 5000 mg to kg, we use the formula $m_{kg}=\frac{m_{mg}}{10^6}$. Substituting $m_{mg} = 5000$ mg, we get $m_{kg}=\frac{5000}{10^6}=0.005$ kg.

Speed is a scalar quantity because it only has magnitude (e.g., 50 km/h). It does not have a direction associated with it. Velocity is a vector quantity because it has both magnitude (e.g., 50 km/h) and direction (e.g., 50 km/h north).

Answer:

The speed of the fluid increases and the pressure of the fluid decreases in the narrow section.