## Orbital Speed Formula :

Orbital Speed V_{orbit }is equal to the product of the gravitational constant G_{(ms}^{-1}_{)} in meter second is multiply by mass of the planet M_{(kg)} in kilogram is divided by radius R_{(cm)} in centimeter. Hence the orbital speed formula has been written as,

**V _{orbit} = √G_{(ms}^{-1}_{)} M_{(kg)} / R_{(cm)}**

Where,

G→ gravitational constant in (ms^{-1})

M → mass of the planet in (kg)

r → radius in (cm).

## Sample Sums :

### Sum1 :

Calculate the orbital speed? The radius is given as 6.5 * 10^{6} m, The mass of an object is given as 5.9722 * 10^{24} kg and the gravitational constant G is 6.67408 * 10^{-11} m^{3} kg^{-1} s^{-2}.

### Solution :

We have,

G = 6.67408 * 10^{-11}

R = 6.5 * 10^{6}

M = 5.9722 * 10^{24}

Using the formula we have,

V = √(GM/R)

= (6.67408 * 10^{-11})(5.9722 * 10^{24})/(6.5 * 10^{6})

= 29.8 km/s.

### Sum2 :

Calculate the orbital speed? The radius is given as 2439.7 km, The mass of an object is given as 0.33 * 10^{24} kg and the gravitational constant G is 6.67408 * 10^{-11} m^{3} kg^{-1} s^{-2}.

### Solution :

We have,

G = 6.67408 * 10^{-11}

R = 2439.7

M = 0.33 * 10^{24}

Using the formula we have,

V = √(GM/R)

= (6.67408 * 10^{-11})(0.33 * 10^{24})/(2439.7)

= 47.4 km/s.