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elena-14-01-66 [18.8K]
3 years ago
7

Grinding quartz crystals down to produce sand is an example of a a. change of state. c. chemical reaction. b. chemical change. d

. physical change.
Physics
1 answer:
seraphim [82]3 years ago
5 0
D. A physical change

The makeup of it is still the same it's just ground up
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Answer:

Explanation:

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Let a is teh acceleration ans T1 and T2 be the tension in the rope.

The moment of inertia of the pulley

I = 0.5 x m3 x R² = 0.5 x 1.5 x 0.09 x 0.09 = 0.006075 kgm²

According to Newton's second law

T1 - m1 g = m1 x a .... (1)

m2 g - T2 = m2 x a ..... (2)

(T2 - T1 ) x R = I x α    

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from (1), (2) and (3)

a = \frac{m_{2}-m_{1}}{m_{1}+m_{2}+\frac{m_{3}}{2}}\times g

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a = 1.78 m/s²

from equation (1)

T1 = m1 ( g + a) = 3 ( 9.8 + 1.78) = 34.77 N

from equation (2)

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