I agree with it.The most widely accepted theory is that the first cells were created by groups of molecules working together to make the basic biomolecules (Carbs, Lipids, Proteins, Nucleic Acids). These biomolecules eventually found each other and supported each other creating cells. Over millions of years these unicellular organisms evolved into multicellular organisms, eventually leading up to humans and other common life forms today.
Personally I think it’s easiest to read over just the definitions over and over and then go back to the words and say oh yeah that’s this definition also make sure u don’t memorize them in order IT WONT BE THAT WAY ON THE TEST anddd quizlet is ur bff bc they usually have any or most sets or vocab
Answer:
A) Cm = 2.232 s/mm²
B) Time taken to solidify = 74.3 seconds
Explanation:
(A) Since a side is 50mm and all sides of a cube are equal, thus, Volume of the cube is;V = 50 x 50 x 50 = 125,000 mm³
There are 6 faces of the cube, thus Surface Area A = 6 x (50 x 50) = 15,000 mm²
So, Volume/Area = (V/A) = 125,000/15,000 = 8.333 mm
Cm is given by the formula; Cm =[Tts] /(V/A)² where Tts is time taken to solidify and it's 155 seconds in the question. Thus;
Cm = 155/(8.333)²= 2.232 s/mm²
(B) For;Cylindrical casting with D = 30 mm and L = 50 mm.;
Volume of cylinder is;
V = (πD²L) /4
So,V = (π x 30² x 50)/4 = 35,343mm³
Surface area of cylinder is;
A = (2πD²)/4 + (πDL)
Thus, A = ((π x 30²)/2) + (π x 30 x 50) = 6126 mm²
Volume/Area is;
V/A = 35,343/6126 = 5.77 mm
Same alloy and mold type was hsed as in a above, thus, Cm is still 2.232 s/mm²
Since Cm =[Tts] /(V/A)²
Making Tts the subject, we have;
Tts =Cm x (V/A)²
Tts = 2.232 x (5.77)² = 74.3 seconds
