-- The area under a velocity/time graph, between two points in time, is the difference in displacement during that period of time.
-- The area under a speed/time graph, between two points in time, is the distance covered during that period of time.
Answer: Question 1: Efficiency is 0.6944
Question 2: speed of similar pump is 2067rpm
Explanation:
Question 1:
Flow rate of pump 1 (Q1) = 300gpm
Flow rate of pump 2 (Q2) = 400gpm
Head of pump (H)= 55ft
Speed of pump1 (v1)= 1500rpm
Speed of pump2(v2) = ?
Diameter of impeller in pump 1= 15.5in = 0.3937m
Diameter of impeller in pump 2= 15in = 0.381
B.H.P= 6.0
Assuming cold water, S.G = 1.0
eff= (H x Q x S.G)/ 3960 x B.H.P
= (55x 300x 1)/3960x 6
= 0.6944
Question 2:
Q = A x V. (1)
A1 x v1 = A2 x V2. (2)
Since A1 = A2 = A ( since they are geometrically similar
A = Q1/V1 = Q2/V2. (3)
V1(m/s) = r x 2π x N(rpm)/60
= (0.3937x 2 x π x 1500)/2x 60
= 30.925m/s
Using equation (3)
V2 = (400 x 30.925)/300
= 41.2335m/s
To rpm:
N(rpm) = (60 x V(m/s))/2 x π x r
= (60 x 41.2335)/ 2× π × 0.1905
= 2067rpm.
The correct answer is - D. 1 percent.
The United States are the biggest consumer of electricity in the world. Because of that the United States are using multiple different sources in order to satisfy the demand for the electricity. The solar energy though accounts for only 1% of the total amount of produced electricity in the country and that is concerning. The biggest concern of course is the environmental one as the majority of the electricity is produced by sources that are polluting the environment. The other concern is that the United States are not using their potential in gaining more electricity from the solar radiation when taken in account that they have very large areas in the country that have a lot of intense solar radiation and clear skies throughout most of the year.
Answer:
space = 66.24 [m]
Explanation:
To solve this problem we must remember that the average speed is defined as the relationship between a space traveled over a certain time.
where:
space [m]
Av = average velocity = 3.6 [m/s]
time = 18.4 [s]
![space = 3.6*18.4\\space = 66.24 [m]](https://tex.z-dn.net/?f=space%20%3D%203.6%2A18.4%5C%5Cspace%20%3D%2066.24%20%5Bm%5D)
