Answer:
Silk fibre is obtained from <u>silkworms</u>
whereas artificial silk is obtained by
chemical treatment of <u>wood pulp/cellulose.</u>
Explanation:
Artificial silk, or rayon, is made from cellulose, obtained from cotton or wood pulp.
So any one of them in 2nd blank is correct.
Answer:
s = 3 m
Explanation:
Let t be the time the accelerating car starts.
Let's assume the vehicles are point masses so that "passing" takes no time.
the position of the constant velocity and accelerating vehicles are
s = vt = 40(t + 2) cm
s = ½at² = ½(20)(t)² cm
they pass when their distance is the same
½(20)(t)² = 40(t + 2)
10t² = 40t + 80
0 = 10t² - 40t - 80
0 = t² - 4t - 8
t = (4±√(4² - 4(1)(-8))) / 2(1)
t = (4± 6.928) / 2 ignore the negative time as it has not occurred yet.
t = 5.464 s
s = 40(5.464 + 2) = 298.564 cm
300 cm when rounded to the single significant digit of the question numerals.
True, scientists often talk to each other to figure out if their results were similar and what they could have done better.
Although, talking to other scientists does have risks, other scientists could copy your work and further better it.
So, your final answer is TRUE, sorry for the long answer, I needed to have a word count about 20 characters and then I got carried away! lol