Answer:
Check the explanation
Explanation:
Question 1.
The secondary current of 250/5 amps CT when 300 amps(rated current of transmission line ) flow in TL is
(5/250 ) X 300 = 6 amps
Question 2
The correct answer to this second question is yes, when Over current relay coil will operate and relay contacts gets close, if the pickup value( Ip) of relay is set as 6 amps in relay. ( because primary current of TL is 1.2 times of CT primary)
Question 3
Tap Block figure (Fig 1) is not available/uploaded in your question.
Answer:
Maximum shear stress is;
τ_max = 1427.12 psi
Explanation:
We are given;
Power = 2 HP = 2 × 746 Watts = 1492 W
Angular speed;ω = 450 rev/min = 450 × 2π/60 rad/s = 47.124 rad/s
Diameter;d = 1 in
We know that; power = shear stress × angular speed
So,
P = τω
τ = P/ω
τ = 1492/47.124
τ = 31.66 N.m
Converting this to lb.in, we have;
τ = 280.2146 lb.in
Maximum shear stress is given by the formula;
τ_max = (τ•d/2)/J
J is polar moment of inertia given by the formula; J = πd⁴/32
So,
τ_max = (τ•d/2)/(πd⁴/32)
This reduces to;
τ_max = (16τ)/(πd³)
Plugging in values;
τ_max = (16 × 280.2146)/((π×1³)
τ_max = 1427.12 psi
Answer:
18 teeth/inch
Explanation:
Given that: i. driver gear has 8 teeth and diametral pitch of 6 teeth/inch.
ii. follower gear has 24 teeth.
Let the followers diametral pitch be represented by x.
Then,
8 teeth ⇒ 6 teeth/inch
24 teeth ⇒ x teeth/inch
So that;
x = 
= 
= 18 teeth/inch
The diametral is 18 teeth/inch
