Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
Home  >>  JEEMAIN and AIPMT  >>  Physics  >>  Class11  >>  Gravitation
0 votes

At what velocity in (km/s) should a body be projected horizontally at a height of 30 km from the ground so that it becomes the satellite of the earth? neglect air friction. (radius of earth is $6370 \;Km$)

\[(a)\;7.6 \quad (b)\;7.9 \quad (c)\;9.8 \quad (d)\;11.2\]
Can you answer this question?

1 Answer

0 votes
Orbital velocity $v_0$ required is given by
$v_0=\sqrt {\large\frac{g_0 R^2}{R+h}}$
$\qquad=\sqrt {\large\frac{9.8 \times (6370 \times 10^3)^2}{(6370+30) \times 10^3}}$$m/s$
$\qquad=7.882 km/s$
$\qquad=7.9 \;km/s$
Hence b is the correct answer.
answered Aug 12, 2013 by meena.p
edited Jun 29, 2014 by lmohan717

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, NEET Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App