As per the Newtons law of gravitation ,the gravitational force between two bodies is given as - $F = G\frac{mm'}{r^{2} }$ where G is the gravitational force constant.

From the above we see that F ∝ mm' and $F\alpha \frac{1}{r^{2} }$

Let the orbital radius of planet A is $r_{1}$ = r and mass of planet is $m_{1}$ .

Let the mass of central star is m .

Hence the gravitational force for planet A is $f_{1} =G \frac{m_{1}*m }{r^{2} }$

For planet B the orbital radius $r_{2} =2r_{1}$ and mass $m_{2} = 3 m_{1}$

Hence the gravitational force $f_{2} =G\frac{m m_{2} }{r^{2} }$

$f_{2} =G\frac{m*3m_{1} }{[2r_{1}] ^{2} }$

$= \frac{3}{4} G\frac{mm_{1} }{r_{1} ^{2} }$

Hence the ratio is $\frac{f_{2} }{f_{1} } = \frac{\frac{3}{4}G mm_{1/r_{1} ^2} }{Gmm_{1}/r_{1} ^2 }$

$=\frac{3}{4}$ [ ans]

3 0

3 years ago

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Difference between inverted and upright microscope

ser-zykov [4K]

An Inverted Microscope gives you more freedom than an upright microscope. Inverted microscopes are very useful to examine the surface of heavy and large sized Items for industrial purposes. Whereas <span>upright microscopes have very limited distance between the table and the objective.</span>

6 0

3 years ago

Compare and contrast the two different types of mechanical waves?

prohojiy [21]

There are longitudinal and transverse. Both types of mechanical waves require a medium, transport energy, and have defined wavelengths, frequencies, and speeds.
Differences are that transverse waves oscillate along a direction perpendicular to the direction of travel (like shaking a rope up and down). Longitudinal waves like oscillations along a spring and sound waves, oscillate back and forth along the direction of travel.

5 0

3 years ago

The objects shown in the following diagrams have different masses and are different distances apart. Which diagram shows the two

sergiy2304 [10]

Answer:

C. 10kg to 10kg

Explanation:

You have to picture to it I think

5 0

2 years ago