Answer:
I want to believe the program is to be written in java and i hope your question is complete. The code is in the explanation section below
Explanation:
import java.util.Date;
public interface Downloadable {
//abstract methods
public String getUrl();
public Date getLastDownloadDate();
}
Answer:
a) 49.95 watts
b) The self locking condition is satisfied
Explanation:
Given data
weight of the square-thread power screw ( w ) = 100 kg = 1000 N
diameter (d) = 20 mm ,
pitch (p) = 2 mm
friction coefficient of steel parts ( f ) = 0.1
Gravity constant ( g ) = 10 N/kg
Rotation of electric power screwdrivers = 300 rpm
A ) Determine the power needed to raise to the basket board
first we have to calculate T
T = Wtan (∝ + Ф ) *
------------- equation 1
Dm = d - 0.5 ( 2) = 19mm
Tan ∝ =
where L = 2*2 = 4
hence ∝ = 3.83⁰
given f = 0.1 , Tan Ф = 0.1. hence Ф = 5.71⁰
insert all the values into equation 1
T = 1.59 Nm
Determine the power needed using this equation
= 
= 49.95 watts
B) checking if the self-locking condition of the power screw is satisfied
Ф > ∝ hence it is self locking condition is satisfied
This question is not complete, the complete question is;
The stagnation chamber of a wind tunnel is connected to a high-pressure air bottle farm which is outside the laboratory building. The two are connected by a long pipe of 4-in inside diameter. If the static pressure ratio between the bottle farm and the stagnation chamber is 10, and the bottle-farm static pressure is 100 atm, how long can the pipe be without choking? Assume adiabatic, subsonic, one-dimensional flow with a friction coefficient of 0.005
Answer:
the length of the pipe is 11583 in or 965.25 ft
Explanation:
Given the data in the question;
Static pressure ratio; p1/p2 = 10
friction coefficient f = 0.005
diameter of pipe, D =4 inch
first we obtain the value from FANN0 FLOW TABLE for pressure ratio of ( p1/p2 = 10 )so
4fL
/ D = 57.915
we substitute
(4×0.005×L
) / 4 = 57.915
0.005L
= 57.915
L
= 57.915 / 0.005
L
= 11583 in
Therefore, the length of the pipe is 11583 in or 965.25 ft
Answer:
1. Industrial revolution was initiated or borne through the production of Steel
2. World War 1 led to the development of Tanks
Explanation:
The production of Steel through the Bessemer Process in the middle of the nineteenth century was a major technological development that spurred the Industrial revolution. This invention led to the widespread use of steel in the production of many things including vehicles and airplanes.
During the First World War in 1914, soldiers found the use of just their armaments in battle as not so productive. This led to the development of Tanks in 1915 that would continue moving towards the enemy even when being shot at.
Answer:
well what do you wanna talk about friend?
Explanation: