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Physics Light Difficulty: Medium

Assertion (A): Small glass beads fixed on traffic signals glow brightly when light falls upon them. Reason (R): Light is totally reflected when the angle of incidence exceeds a certain critical value and light travelling in a denser medium is reflected from a rarer medium. Which of the following technologies has been used by China for its 'artificial sun'? 'W'h'a't' 'i's' 't'h'e' 'r'e's'i's't'a'n'c'e' '('i'n' 'Ω')' 'o'f' 'a'n' 'e'l'e'c't'r'i'c'a'l' 'c'o'm'p'o'n'e'n't',' 'i'f' 'a' 'c'u'r'r'e'n't' 'o'f' '0'.'1'A' 'p'a's's'e's' 't'h'r'o'u'g'h' 'i't' 'o'n' 'a'p'p'l'i'c'a't'i'o'n' 'o'f' '5'V' 'o'f' 'p'o't'e'n't'i'a'l' 'd'i'f'f'e'r'e'n'c'e' 'a'c'r'o's's' 'i't'?' Which force maintains the structure of our solar system? An electric bulb of 60 W is used 6 h per day. Calculate the energy used by the bulb in one day.