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
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What is the mean free path of a gas of hard spheres of radius 2.00 × 10-9 m when the number of spheres per volume is 3.00 × 1019 m-3?
A) 1.17 × 10-4 m B) 4.00 × 10-9 m C) 9.76 × 10-5 m D) 1.88 × 10-3 m E) 4.69 × 10-4 m
______________ has the general formula (C6H10O5)n, where n may take on values up to 3000
Fill in the blank(s) with correct word
An electron in a TV picture tube is accelerated through a potential difference of 20 kV before it hits the screen. What is the kinetic energy of the electron in electron volts? (1 eV = 1.6 × 10^-19 J)
a. 6.25 × 10^22 eV c. 2.0 × 10^4 eV b. 1.0 × 10^4 eV d. 3.2 × 10^-22 eV
_______________ theoretical assumptions on quantization overcame the difficulty with a major problem with understanding blackbody radiation.
A. Hertz's B. Planck's C. Einstein's D. Maxwell's E. Bohr's