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A Semicircular wire has a mass M and length L . A particle of mass m is placed at the centre of the circle.Find the gravitational attraction on the particle due to wire.Ans=2(pie)GMm/L2
two particles of equal mass m go around a circle of radius R under the action of their mutual gravitational attraction . the speed v of each particle is
1)1/2*(Gm/R)1/2
2)1/2R*(1/Gm)1/2
Three equal masses of each m kg are fixed at the vertices of an equilateral triangle ABC.
a)What is the force acting on a mass 2m placed at the centroid G of the triangle.
b)What is the force if the mass at the vertex Ais doubled?
[AG=BG=CG=1m]
textbook page no. 187 example: 8.2please explain to me properly i am not able to understand that.
a body weighs 90 kgf on surface of earth.how much it will weigh on the surface of mars whose mass is 1/9 and radius is 1/2 of that of earth ?
4 particles having masses m,2m,3m and 4m are placed at the 4 corners of a square of edge a.Find the gravitational acting on a particle of mass m placed at the center?
A solid sphere of uniform density and radius R apies a grav force of attraction =F1 on a particle placed at A distance of 2R fro the centre of the sphere . A spherical cavity of radius R/2 is now made in the sphere which applies a force F2 on the same particle, FI/F2?
an artificial satellite is moving around earth in a circular orbit equal to one fourth the escape speed of a body , from the surface of earth .the hgt of satellite above earth's surface is (R = radius of earth)
ans: 7R
why?
expression for escape velocity of an object on the surface of earth.
2) A tunnel is dug along a diameter of the earth. If M and R are the mass and radius respectively of earth, then the force on a particle of mass 'm' placed in the tunnel at a distance r from the center is
if mass of earth decreases by 25% and its radius increases by 50% , then acceleration due to gravity at its surface decreases by nearly
ans:67%
how?
an object of mass M is divided into two parts , which are placed at distance d. if gravitational force of attraction is max between parts, then find the ratio of mass of both parts.
ans: 1:1
???
two point objects of mass 2x and 3x are seprated by a distance r . keeping the distance fixed , how much mass should be transferred from 3x to 2x , so that gravitational force between them becomes max..??
ans: x/2
plz explain
the distance between two planets from sun are 1013 and 1012m respectively. find the ratio of time period and speed of two planets.
why does a satellite need no fuel to go around the earth
if the distance between the earth nad the sun is reduced to half of its present value, what would be the number of days inone year?
A simple pendulum has a time period T1 when on the Earth's surface and T2 when taken to a height R above the Earth's surface where R is the radius of the Earth.What is the value of T2/T1?
If the radius of the earth shrinks by 2percent, mass remaining the same the how would the value of acceleration due to gravity change????
in percent
plz reply as soon as u can :):)
energy required to move a body of mass m from an orbit of radius 2R to 3R is [ M= mass of earth , R = radius od earth]
1) GMm/3R
2)GMm/12R
3)GMm/18R
4)GMm/6R
3 uniform spheres each having a mass M and radius a are kept in such a way that each touches the other two.Find the magnitude of the gravitational force on any of the spheres due to the other two.
A double star is a system of two stars (say masses m1 and m2) moving around the centre of inertia of the sustem due to gravitation . Then , ratio of sweeps area of atar of mas m1 to the star of the mass m2is .............................
Ans given in book is : m22/m12
the gravitational potential energy of a body at a distance r from the centre of the earth is U. its weight at a distance 2r from the centre of the earth is
a) U/r
b) U/2r
c) U/4r
d) U/(r*sqrt 2)
what is the minimum energy required to launch a 1500kg satellite from the earth's surface to an altitude of 320km. (radius of earth=6.4*10^6m and mass of the earth=6*10^24kg)
if the earth stops rotating about axis, the accelerelation due to gravity will remain unchanged at..
a) equator
b) latitude 45o
c) latitude 60o
d) poles
If earth has amass 9 times and radius 4 times than that of a planet 'P'. Calculate the escape velocity of the planet P if its value on earth is 11.2 km/s.
Four particles of equal mass are moving round a circle of radius r due to their mutual gravitational attraction.Find the angular velocity of each particle?
a 400kg satellite is in a circular orbit of radius 2 Re about the earth. how much energy is required to transfer it to a circular orbit of radius 4 Re ? what are the changes in the kinetic nd potential energies?
al satellite moving in a circular orbit around the Earth has a total (K.E. + P.E.) = E0. Its potential energy is:
E0
1.5 E0
2 E0
A satellite is put in an orbit just above the earths atmosphere with a velocity √(1.5) times the velocity for a circular orbit at that height. The initial velocity imported is horizontal. What would be the maximum distance of the satellite from the surface of the earth when it is the orbit?
Ans in book is 2R
what is the phenomenon of capillarity ? derive an expression for the rise of liquid in a capillary tube .
The distance of Saturn and neptune from the sun is nearly 10^12 and 10^13 m, respectively. Assuming they move in circular orbits their time periods wil bein the ratio?
how far above the earth's surface does the value of g becomes 20% of its value on the surface?
Abody of mass 'm' is taken from the earth's surface to the height equal to twice the redius (R) of the earth . The change in potential energy of the body will be:- (a) 1/3mgR
(b) mg2R (C) 2/3 mgR (D) 3mgR PLEASE EXPLAIN ME .........SIR....
Q0 4 particles each of mass m are at the corner of a square of side a calculate the net gravitational force acting on any mass due to other three.
a satellite of mass 1000 kg moves in a circular orbit of radius 7000 km round the earth , calculate the total energy required to place the satellite in orbit from earths surface. assuming it is initially at rest.
please answer quickly !!!!!!!!
The Sun rotates around itself once in 27 days. If it were to expand to twice its present diameter, what would be its new period of revolution ?
Q) A body weighs 72N on the surface of the earth, What is the gravitational force due to earth at a height equal to half the radius of the earth from the surface?
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Syllabus
A Semicircular wire has a mass M and length L . A particle of mass m is placed at the centre of the circle.Find the gravitational attraction on the particle due to wire.Ans=2(pie)GMm/L2
two particles of equal mass m go around a circle of radius R under the action of their mutual gravitational attraction . the speed v of each particle is
1)1/2*(Gm/R)1/2
2)1/2R*(1/Gm)1/2
Three equal masses of each m kg are fixed at the vertices of an equilateral triangle ABC.
a)What is the force acting on a mass 2m placed at the centroid G of the triangle.
b)What is the force if the mass at the vertex Ais doubled?
[AG=BG=CG=1m]
textbook page no. 187 example: 8.2please explain to me properly i am not able to understand that.
a body weighs 90 kgf on surface of earth.how much it will weigh on the surface of mars whose mass is 1/9 and radius is 1/2 of that of earth ?
4 particles having masses m,2m,3m and 4m are placed at the 4 corners of a square of edge a.Find the gravitational acting on a particle of mass m placed at the center?
A solid sphere of uniform density and radius R apies a grav force of attraction =F1 on a particle placed at A distance of 2R fro the centre of the sphere . A spherical cavity of radius R/2 is now made in the sphere which applies a force F2 on the same particle, FI/F2?
an artificial satellite is moving around earth in a circular orbit equal to one fourth the escape speed of a body , from the surface of earth .the hgt of satellite above earth's surface is (R = radius of earth)
ans: 7R
why?
expression for escape velocity of an object on the surface of earth.
2) A tunnel is dug along a diameter of the earth. If M and R are the mass and radius respectively of earth, then the force on a particle of mass 'm' placed in the tunnel at a distance r from the center is
A) GMmr/R^3 B) GMm/rR^3 C) GMmR^3/r D) GMmr/R^2if mass of earth decreases by 25% and its radius increases by 50% , then acceleration due to gravity at its surface decreases by nearly
ans:67%
how?
A) 1043 B)10-43 C)10-35 D)1035
an object of mass M is divided into two parts , which are placed at distance d. if gravitational force of attraction is max between parts, then find the ratio of mass of both parts.
ans: 1:1
???
two point objects of mass 2x and 3x are seprated by a distance r . keeping the distance fixed , how much mass should be transferred from 3x to 2x , so that gravitational force between them becomes max..??
ans: x/2
plz explain
the distance between two planets from sun are 1013 and 1012m respectively. find the ratio of time period and speed of two planets.
why does a satellite need no fuel to go around the earth
if the distance between the earth nad the sun is reduced to half of its present value, what would be the number of days inone year?
A simple pendulum has a time period T1 when on the Earth's surface and T2 when taken to a height R above the Earth's surface where R is the radius of the Earth.What is the value of T2/T1?
If the radius of the earth shrinks by 2percent, mass remaining the same the how would the value of acceleration due to gravity change????
in percent
plz reply as soon as u can :):)
energy required to move a body of mass m from an orbit of radius 2R to 3R is [ M= mass of earth , R = radius od earth]
1) GMm/3R
2)GMm/12R
3)GMm/18R
4)GMm/6R
3 uniform spheres each having a mass M and radius a are kept in such a way that each touches the other two.Find the magnitude of the gravitational force on any of the spheres due to the other two.
A double star is a system of two stars (say masses m1 and m2) moving around the centre of inertia of the sustem due to gravitation . Then , ratio of sweeps area of atar of mas m1 to the star of the mass m2is .............................
Ans given in book is : m22/m12
the gravitational potential energy of a body at a distance r from the centre of the earth is U. its weight at a distance 2r from the centre of the earth is
a) U/r
b) U/2r
c) U/4r
d) U/(r*sqrt 2)
what is the minimum energy required to launch a 1500kg satellite from the earth's surface to an altitude of 320km. (radius of earth=6.4*10^6m and mass of the earth=6*10^24kg)
if the earth stops rotating about axis, the accelerelation due to gravity will remain unchanged at..
a) equator
b) latitude 45o
c) latitude 60o
d) poles
If earth has amass 9 times and radius 4 times than that of a planet 'P'. Calculate the escape velocity of the planet P if its value on earth is 11.2 km/s.
Four particles of equal mass are moving round a circle of radius r due to their mutual gravitational attraction.Find the angular velocity of each particle?
a 400kg satellite is in a circular orbit of radius 2 Re about the earth. how much energy is required to transfer it to a circular orbit of radius 4 Re ? what are the changes in the kinetic nd potential energies?
al satellite moving in a circular orbit around the Earth has a total (K.E. + P.E.) = E0. Its potential energy is:
E0
1.5 E0
2 E0
E0
A satellite is put in an orbit just above the earths atmosphere with a velocity √(1.5) times the velocity for a circular orbit at that height. The initial velocity imported is horizontal. What would be the maximum distance of the satellite from the surface of the earth when it is the orbit?
Ans in book is 2R
what is the phenomenon of capillarity ? derive an expression for the rise of liquid in a capillary tube .
The distance of Saturn and neptune from the sun is nearly 10^12 and 10^13 m, respectively. Assuming they move in circular orbits their time periods wil bein the ratio?
how far above the earth's surface does the value of g becomes 20% of its value on the surface?
Abody of mass 'm' is taken from the earth's surface to the height equal to twice the redius (R) of the earth . The change in potential energy of the body will be:- (a) 1/3mgR
(b) mg2R (C) 2/3 mgR (D) 3mgR PLEASE EXPLAIN ME .........SIR....
Q0 4 particles each of mass m are at the corner of a square of side a calculate the net gravitational force acting on any mass due to other three.
a satellite of mass 1000 kg moves in a circular orbit of radius 7000 km round the earth , calculate the total energy required to place the satellite in orbit from earths surface. assuming it is initially at rest.
please answer quickly !!!!!!!!
The Sun rotates around itself once in 27 days. If it were to expand to twice its present diameter, what would be its new period of revolution ?
Q) A body weighs 72N on the surface of the earth, What is the gravitational force due to earth at a height equal to half the radius of the earth from the surface?