To find the ratio of planetary speeds Va/Vb we need the orbital velocity formula:

V=√({G*M}/R), where G is the gravitational constant, M is the mass of the distant star and R is the distance of the planet from the star it is orbiting.

So Va/Vb=[√( {G*M}/Ra) ] / [√( {G*M}/Rb) ], in our case Ra = 7.8*Rb

Va/Vb=[ √( {G*M}/{7.8*Rb} ) ] / [√( {G*M}/Rb )], we put everything under one square root by the rule: (√a) / (√b) = √(a/b)

Va/Vb=√ [ { (G*M)/(7.8*Rb) } / { (G*M)/(Rb) } ], when we cancel out G, M and Rb we get:

Va/Vb=√(1/7.8)/(1/1)=√(1/7.8)=0.358 so the ratio of Va/Vb = 0.358.

6 0

3 years ago

Preschool girls and boys do not differ in the amount of muscle they have<br> 1) True<br> 2) False

Marina86 [1]

Explanation:

False...............

3 0

3 years ago

Our eyes can see light with an angular resolution of about 1’—equivalent to about a third of a millimeter at arm’s length. Suppo

olya-2409 [2.1K]

Answer:

We would not be able to make our way around the earth's surface, to read, to sculpt or to create technology because we cannot see!

Explanation:

The minimum angular separation that can be distinguished by an eye gives the angular resolution of the eye.

Given that the Angular resolution with infrared radiation is = $1.0^0$ equal to $60'$

This resolution is very much greater than that of the eye $(1')$

The angular resolution that our eyes can see is about $\frac{1}{3}mm$ at arms length

Angular resolution of infrared = $\frac{1}{3} * 60 = 20mm$ at arms length

We therefore cannot read, sculpt or create technology because we cannot see.

7 0

3 years ago

What is meant by a quark’s “flavor”?

Viktor [21]

Answer:

Explanation:

because a quark have many kinds of flavor

7 0

3 years ago

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