Answer: Objects that are warmer emit more energetic radiation than those that are cooler and so they cool faster. Therefore, in the absence of an external heat ...
Explanation:
Answer:
Explanation:
What is Henry's answer to the objection that the colonists are not ready to fight against the British? Henry says that there are enough people with the motivation to achieve independence, which he says will easily defeat any other country. He also says that God is on their side and will help them through the battle.
I was playing my game mom said go feed the dogs i said no the i thought about it and i need to feed them
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
