Gamma radiation could be used to sterilize plastic petri plates in a plastic wrapper.
Answer: Option E
<u>Explanation:
</u>
It is known that radioactive radiations have greater ionizing powers compared to other electromagnetic radiations. Among the radioactive radiations, gamma rays are the most ionizing radiation.
So they are widely used in sterilizing process. As the penetration power of gamma is more compared to alpha and beta, in order to kill microorganisms gamma radiations are used.
When plastic petri plates wrapped with plastic are bombarded or sterilizing with gamma rays, the rays will ionise the micro-organism. Thus mutilating their DNA and preventing their reproduction.
Answer:
The rate of transfer of heat is 0.119 W
Solution:
As per the question:
Diameter of the fin, D = 0.5 cm = 0.005 m
Length of the fin, l =30 cm = 0.3 m
Base temperature, 
Air temperature, 
k = 388 W/mK
h = 
Now,
Perimeter of the fin, p = 
Cross-sectional area of the fin, A = 
A = 
To calculate the heat transfer rate:
where
Now,
The force of gravity the masses exert on each other. If one of the masses is doubled , the force of gravity between the objects is doubled. Increases , the force of gravity decreases.
