Question

19. Find the velocity of a satellite at height 80 km from
earth, if the radius of earth is 6400 km

(1) 7 km/s
(2) 8 km/s
(3) 7.84 km/s
(4) 11.2 km/s​

Answer 1

Answer:

3 > 7.84

Explanation:

As we know that speed of a satellite is its orbit is

V = √ GM/R

Here => G = 6.67×10-¹¹Nm²/kg²

M = 5.98× 10²⁴kg

=> R = 6400

=> So √ 6.67×10-¹¹× 5.98×10²⁴/64×10⁴

= 7.84 km/s