info@clay6.com
+91-9566306857
(or)
+91-9176170648
Ask Questions, Get Answers
Menu
X
JEEMAIN Crash Practice
15 Test Series
NEET Crash Practice
15 Test Series
CBSE XII
Math
JEEMAIN
Math
Physics
Chemistry
Practice Test Series
CBSE XI
Math
NEET
Physics
Chemistry
Biology - XII
Biology - XI
Olympiad class V
Math - 5 Test Series
Olympiad class VI
Math - 5 Test Series
CBSE XII Board Exam Series
BES Math
BES Physics
BES Chemistry
BES Biology
studyplans
JEEMAIN Crash Practice
15 Test Series
NEET Crash Practice
15 Test Series
CBSE XII
Math
JEEMAIN
Math
Physics
Chemistry
Practice Test Series
CBSE XI
Math
NEET
Physics
Chemistry
Biology - XII
Biology - XI
Olympiad class V
Math - 5 Test Series
Olympiad class VI
Math - 5 Test Series
CBSE XII Board Exam Series
BES Math
BES Physics
BES Chemistry
BES Biology
mobile
exams
ask
sample papers
tutors
pricing
login
X
ASK
Home
>>
JEEMAIN and NEET
>>
Physics
>>
Class11
>>
Gravitation
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 $6370 \;Km$)
\[(a)\;7.6 \quad (b)\;7.9 \quad (c)\;9.8 \quad (d)\;11.2\]
jeemain
physics
class11
unit6
gravitation
q25
medium
Share
asked
Aug 12, 2013
by
meena.p
retagged
Jul 10, 2014
Please
log in
or
register
to add a comment.
Please
log in
or
register
to answer this question.
1 Answer
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
Please
log in
or
register
to add a comment.
Related questions
A particle is projected from the surface of earth with an initial speed of 4 km/s . Find the maximum height attained by the particle.Radius of earth =6400 km and $g= 9.8 m/s^2$
jeemain
physics
class11
unit6
gravitation
q34
medium
asked
Aug 20, 2013
by
meena.p
1
answer
A rocket is launched with velocity 10 km/s if radius of earth is R, then maximum height attained by it will be
jeemain
physics
class11
unit6
gravitation
q15
easy
asked
Aug 10, 2013
by
meena.p
1
answer
If a body is to be projected vertically upwards from the surface of the earth to reach a height nR then the velocity with which it is to be projected is
jeemain
physics
class11
unit6
gravitation
q82
difficult
asked
Aug 26, 2013
by
meena.p
1
answer
A satellite revolving in a circular equatorial orbit of radius $r= 2 \times 10 ^4 km$ from west to East appears over a certain point at the equator every $11.6$ hours. Calculate the actual angular velocity of the satellite
jeemain
physics
class11
unit6
gravitation
q51
medium
asked
Aug 22, 2013
by
meena.p
1
answer
At what height from the ground will the value of 'g' be the same as that in 10 km deep mine below the surface of earth
jeemain
physics
class11
unit6
gravitation
q58
easy
asked
Aug 23, 2013
by
meena.p
1
answer
A satellite of mass m is orbiting the earth at a height 'h' from its surface. If M is Mass of the earth and R its radius then how much energy must be spent to pull the satellite out of the earth's gravitational field?
jeemain
physics
class11
unit6
gravitation
q54
easy
asked
Aug 22, 2013
by
meena.p
1
answer
A geostationary satellite is at a height h above the surface of the earth If R is radius of earth 1) The mimimum coaltitude on earth upto which the satellite can be used for communication is $\sin ^{-1} \bigg(\large\frac{R}{R+a}\bigg)$ 2) The maximum coaltitude on earth upto which the satellite can be used for communication is $\sin ^{-1} \bigg(\large\frac{R}{R+h}\bigg)$ 3) Area of earth escaped from this satellite is given by $ (2 \pi R^2(1+\sin \theta)$ 4) Area of earth escaped from this satellite is given by $ (2 \pi R^2(1+\cos \theta)$
jeemain
physics
class11
unit6
gravitation
q43
difficult
asked
Aug 21, 2013
by
meena.p
1
answer
Ask Question
Tag:
Math
Phy
Chem
Bio
Other
SUBMIT QUESTION
►
Please Wait
Take Test
JEEMAIN Crash Practice
15 Test Series
NEET Crash Practice
15 Test Series
JEEMAIN
350+ TESTS
NEET
320+ TESTS
CBSE XI MATH
50+ TESTS
CBSE XII MATH
80+ TESTS
...
close