Electronic signals are converted into a 'ray of light' -
Given:
Shaft Power, P = 7.46 kW = 7460 W
Speed, N = 1200 rpm
Shearing stress of shaft, 
= 30 MPa
Shearing stress of key, 
= 240 MPa
width of key, w = 
d is shaft diameter
Solution:
Torque, T = 
where,
= 59.365 N-m
Now,
d = 0.0216 m
Now,
w = = 
= 5.4 mm
Now, for shear stress in key
= 
we know that
T = 
= F. 
⇒ = 
⇒ 
= 
length of the rectangular key, l = 4.078 mm
Answer:
Iodine , caesium , strontium ,Plutonium
Explanation:
The isotopes of four main elements which include Iodine , caesium , strontium ,Plutonium contributed mainly to contamination in the Chernobyl accident which involved the release of harmful radioactive radiation into the environment.
The accident occurred in 1986 at Chernobyl , Ukraine as a result of errors made in the design of the reactor and inexperienced hands handling it.
This led to hundreds of death and negative effects on living and the environment around the area.
30km. 24 the first two hours and 6 the half hour
It’s due to the refraction of light rays as they traverse the boundary between water and air. The greater the viewing angle, the more the bending of the light and therefore the less the apparent depth. An object placed in a denser medium, when viewed from rarer medium appears to be at a lesser depth than its real depth due to refraction of light.
