Draw the distance time graph for a body at rest

Water at 20 C flows through a 5-cm-diameter pipe that has a 180 vertical bend, as in Fig. P3.43. The total length of pipe betwee

Nataliya [291]

Answer:

F = 749 [N]

Explanation:

We must give full information on this problem, as well as the question that needs to be resolved.

Water at 20°C flows through a 5-cm-diameter pipe that has a 180° vertical bend. The total length of pipe between flanges 1 and 2 is 75 cm. When the weight flow rate is 230 N/s,

P1=165kPa

and

P2=134kPa

Neglecting pipe weight, determine the total force that the flanges must withstand for this flow.

We must make a U-shaped body diagram of the pipe in order to visualize the forces acting according to the pressures and the area of the pipe.

Then by means of the second law of motion of Newton, which says that the sum of the forces must be equal to the product of mass times acceleration, we can find the force Fp

Let us remember that pressure is defined as the divided force over the area, therefore:

F = P *A

where:

P = pressure

A = area

The product of the mass by acceleration, is equal to the product of the speed of the fluid by the mass flow, since we know the weight of the fluid we can find its mass flow.

$W_{flow}=230[N/s]\\W_{flow} =g*m_{flow}\\m_{flow} = W_{flow} / g\\m_{flow} = 230/9.81\\m_{flow}= 23.45[kg/s]$

In the function of the mass flow, we can find the velocity of the fluid, as we also know the diameter of the pipe

$m_{flow} = density*v*A\\where\\density = 1000[kg/m^{3}]\\ v= velocity[m/s]\\A = area [m^{2}]\\v=\frac{m_{flow}}{density*A} \\v=\frac{23.45}{1000*\frac{\pi}{4}*(5*10^{-2})^{2} } \\v= 11.94 [m/s]$

We know that the atmospheric pressure is equal to:

$P_{atm} = 101.325[kpa]$

The value of the pipe area is calculated for a circular section

$A = \frac{\pi}{4} * (0.05)^{2}\\ A = 0.00196[m^{2} ]$

The resultant force is 749 [N]

The solution of the equations and the free body diagram can be seen in the attached picture.

3 0

3 years ago

For the population, scores on the test are normally distributed with μ = 70 and σ = 15. The sample of n = 25 students had a mean

AysviL [449]

Answer:

$z=\frac{75-70}{\frac{15}{\sqrt{25}}}=1.67$

$p_v =2*P(t_{24}>1.67)=0.108$

If we compare the p value and the significance level given $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we FAIL to reject the null hypothesis, and the the actual mean is not significant different from 70.

Explanation:

1) Data given and notation

$\bar X=75$ represent the sample mean

$\sigma=15$ represent the standard deviation for the population

$n=25$ sample size

$\mu_o =70$ represent the value that we want to test

$\alpha=0.05$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to determine if the mean is different from 70, the system of hypothesis would be:

Null hypothesis: $\mu = 70$

Alternative hypothesis: $\mu \neq 70$

We know the population deviation, so for this case is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$z=\frac{75-70}{\frac{15}{\sqrt{25}}}=1.67$

Calculate the P-value

First we need to calculate the degrees of freedom given by:

$df=n-1=25-1=24$

Since is a two tailed test the p value would be:

$p_v =2*P(t_{24}>1.67)=0.108$

Conclusion

If we compare the p value and the significance level given $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we FAIL to reject the null hypothesis, and the the actual mean is not significant different from 70.

3 0

4 years ago

which term describes soil that is able to transmit water? a. permeable b. horizontal c. biotic d. aggregate

Hatshy [7]

The answer would be permeable i know this because i just took the test on apex.

7 0

3 years ago

Read 2 more answers

A person is filling a knee-high bucket with water using a garden hose and holding it such that water discharges from the hose at

Serggg [28]

Answer:

Yes i am agree with this suggestion

Explanation:

Given that we have to assume that there is no any frictional affects.

As we know that when height increases then the discharge level will decreases when discharge level decreases then the time of filling for the bucket will increase.So the bucket will fill faster if the hose lowered until knee level.

Yes i am agree with this suggestion

8 0

3 years ago

When the north pole of a magnet is moved towards the center of a loop of wire containing a galvanometer, the needle of the galva

andriy [413]

Answer:

Moving the magnet away from the center of the loop with its south pole facing the center of the loop.

Explanation:

Electromagnetic induction is due to a rapidly changing magnetic field, or loop area. The poles of the magnet induce current in the loop but in the opposite direction, depending on the direction of their relative motion. An approaching north pole will induce an anticlockwise current in the loop, while an approaching south pole will do the reverse. To get the galvanometer to flicker in the same direction as of that when the north pole was approaching, we move the magnet away from the center of the loop with its south pole facing the center of the loop.

6 0

3 years ago

Draw the distance time graph for a body at rest​

Draw the distance time graph for a body at rest