Question

An artificial satellite is moving in a circular orbit of radius
42250 km. Calculate its speed if it takes 24 hours to revolve
around the earth.
​

Answer 1

Answer:

The speed of an object moving in a circular orbit is given by formula:

$\star\boxed{\green{v=\frac{2\pi r}{t}}}$

here,

speed,v = ? (to be calculated)

Radius,r = 42250 km

Time,t = 24 h

Now, putting these values in the above formula we get :

$\implies \: speed = \frac{2 \times 22 \times 42250}{7 \times 24} \\ \implies \: speed = 11065.4km {h}^{ - 1}$

we can convert this speed from kilometers per hours to kilometers per second by dividing it by the number of seconds in 1 hour (which is 60*60).Thus:

$v = \frac{11065.4}{60 \times 60} \\ \implies \: v = 3.07km {s}^{ - 1}$

Answer 2

Given :

• An artificial satellite is moving in a circular orbit of radius42250 km.

To Find :

• Calculate its speed if it takes 24 hours to revolve around the earth.

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Solution :

Distance covered by the satellite in 24 hours,

s = 2πr

s = 2 × 3.14 × 42250

s = 265464.58 km

Therefore, the speed of satellite :

v = Distance travelled / time taken

v = 265464.58 / 24 × 3600

v = 3.07 km s-¹

Therefore, the speed it takes 24 hours to revolve around the earth is 3.07 kms-¹.