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FromTheMoon [43]

2 years ago

8

A light-year is a unit of a. time. c. mass. b. distance. d. density. please select the best answer from the choices provided a b

c d

2 answers:

11111nata11111 [884]2 years ago

3 0

Answer:

distance

Explanation:

it is the distance traveled by light in one year

Ray Of Light [21]2 years ago

3 0

B. Distance

A light-year has a bit of a deceiving name. Despite the fact that it seems to imply it is a measure of time, this is not of fact correct. A light-year refers to how far light can travel within a year. One light year is approximately 6 trillion miles. Light years are used to measure extremely far distances such as how far the sun is from other stars, or how far away other exoplanets (planets outside our solar system) are.

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A railroad car having a mass of 17.5 Mg is coasting at 1.5 m/s on a horizontal track. At the same time another car having a mass

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Answer:

Then final velocity of the coupled system of cars will be 0.58 m/s

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luda_lava [24]

Answer:

$\frac{a_{r,earth}}{a_{r,mars}} = 2.325$

Explanation:

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$a_{r} = \frac{v^{2}}{R}$

Since planet has translation at constant speed, this formula is applied to compute corresponding speeds:

$v=\frac{2\pi\cdot r}{\Delta t}$

Earth:

$v_{earth} = \frac{2\pi\cdot (149.6\times 10^{9}\,m)}{(365\,days)\cdot(\frac{24\,hours}{1\,day} )\cdot(\frac{3600\,s}{1\,h} )}$

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Mars:

$v_{mars} = \frac{2\pi\cdot (227.9\times 10^{9}\,m)}{(687\,days)\cdot(\frac{24\,hours}{1\,day} )\cdot(\frac{3600\,s}{1\,h} )}$

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$a_{r,earth} = \frac{(29806.079\,\frac{m}{s} )^{2}}{149.6\times 10^{9}\,m}$

$a_{r,earth} = 5.939\times 10^{-3}\,\frac{m}{s^{2}}$

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$a_{r,mars} = 2.554\times 10^{-3}\,\frac{m}{s^{2}}$

The ratio of Earth's centripetal acceleration to Mars's centripetal acceleration is:

$\frac{a_{r,earth}}{a_{r,mars}} = \frac{5.939}{2.554}$

$\frac{a_{r,earth}}{a_{r,mars}} = 2.325$

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