Answer:
(d) all of the above
Explanation:
before cutting the screw threads the operator should lubricate all of the machine parts given in the option that is lead screw and gearbox , the ways and the cross slide and the carriage and half-nuts. we should use lubrication because it reduces the overall system friction and if friction is reduced then heat generated due to friction is also decreases which is beneficial
so option (D) will be correct because we need lubricate in all the given parts
Answer:
R = 31.9 x 10^(6) At/Wb
So option A is correct
Explanation:
Reluctance is obtained by dividing the length of the magnetic path L by the permeability times the cross-sectional area A
Thus; R = L/μA,
Now from the question,
L = 4m
r_1 = 1.75cm = 0.0175m
r_2 = 2.2cm = 0.022m
So Area will be A_2 - A_1
Thus = π(r_2)² - π(r_1)²
A = π(0.0225)² - π(0.0175)²
A = π[0.0002]
A = 6.28 x 10^(-4) m²
We are given that;
L = 4m
μ_steel = 2 x 10^(-4) Wb/At - m
Thus, reluctance is calculated as;
R = 4/(2 x 10^(-4) x 6.28x 10^(-4))
R = 0.319 x 10^(8) At/Wb
R = 31.9 x 10^(6) At/Wb
The modern hydraulic lifts make use of biodegradable fluid to transmit hydraulic power
<em>Question: The options are left out in the question. The details and facts about the modern hydraulic lift are presented here</em>
<em />
Details about the modern hydraulic lifts include;
The development of the modern hydraulic occurred in the Industrial Revolution to perform task done previously by steam powered elevators
The power of the hydraulic lift come from the hydraulic cylinder known as the actuator, which in turn is powered by pressurized hydraulic fluid such as oil
The hydraulic fluid is pushed by a piston rod through which energy is capable of being transferred, such that the applied force is multiplied, to provide more power for lifting
<u>Facts about the modern hydraulic lifts include;</u>
- The dry motor in the modern hydraulic lift is more efficient and consumes 20% less energy
- It comprises of valves that are controlled electronically such that the response is much rapid and the energy consumption is reduced by a further 20%
- The cars used in the modern lift are lighter, as well as the slings, which reduces the power usage by 20%
- It makes use of chemicals which are environmentally friendly as hydraulic fluid
- The flash point of the fluid used is higher, as well as it posses 50% lower compressibility as well elasticity
Learn more here:
brainly.com/question/16942803
Answer:
7.9 kilometers per second
Explanation: