Two twin sisters, Gwen and Jackie, are both 20 years old in the year 2050. Jackie takes off on a round-trip to Vega, 25 light-years away. She travels at an average speed close to the speed of light, say, 0.9999c. According to Gwen back on Earth, about how long does it take Jackie to reach Vega?

A) about 25 years
B) about a month
C) about 10 years
D) about 100 years


A) about 25 years

Physics & Space Science

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______________ has the general formula (C6H10O5)n, where n may take on values up to 3000

Fill in the blank(s) with correct word

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a. 6.25 × 10^22 eV c. 2.0 × 10^4 eV b. 1.0 × 10^4 eV d. 3.2 × 10^-22 eV

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_______________ theoretical assumptions on quantization overcame the difficulty with a major problem with understanding blackbody radiation.

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