Recent questions in Physics

0 votes

0 answers

Find the potential energy of a system of four particles placed at the vertices of a square of side l. Also obtain the potential at the centre of the

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Two uniform solid spheres of equal radii R, but mass M and 4 M have a centre to centre separation 6 R, as shown in Fig. . The two spheres are held fixed. A projectile of mass m is projected from the surface of the sphere of mass M directly towards the centre of the second sphere. Obtain an expression for the minimum speed v of the projectile so that it reaches the surface of the second sphere.

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

The planet Mars has two moons, phobos and delmos. (i) phobos has a period 7 hours, 39 minutes and an orbital radius of `9.4 ×10^3` km. Calculate the mass of mars. (ii) Assume that earth and mars move in circular orbits around the sun, with the martian orbit being 1.52 times the orbital radius of the earth. What is the length of the martian year in days

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Weighing the Earth : You are given the following data: g = 9.81 `ms^(–2)`,RE = `6.37×10^6` m, the distance to the moon R = `3.84×10^8` m and the time period of the moon’s revolution is 27.3 days. Obtain the mass of the Earth `M_E` in two different

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Express the constant k of Eq. (8.38) in days and kilometres. Given k = `10^(–13)` `s^2` `m^(–3)`. The moon is at a distance of `3.84 × 10^5` km from the earth. Obtain its time-period of revolution in

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

A 400 kg satellite is in a circular orbit of radius `2R_E` about the Earth. How much energy is required to transfer it to a circular orbit of radius `4R_E` ? What are the changes in the kinetic and potential energies

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Answer the following : You can shield a charge from electrical forces by putting it inside a hollow conductor. Can you shield a body from the gravitational influence of nearby matter by putting it inside a hollow sphere or by some other means

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Answer the following : An astronaut inside a small space ship orbiting around the earth cannot detect gravity. If the space station orbiting around the earth has a large size, can he hope to detect gravity

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Answer the following : If you compare the gravitational force on the earth due to the sun to that due to the moon, you would find that the Sun’s pull is greater than the moon’s pull. (you can check this yourself using the data available in the succeeding exercises).

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Choose the correct alternative : (a) Acceleration due to gravity increases/decreases with increasing altitude. (b) Acceleration due to gravity increases/decreases with increasing depth (assume the earth to be a sphere of uniform density). (c) Acceleration due to gravity is independent of mass of the earth/mass of the body. (d) The formula –G Mm(1/`r_2` – 1/`r_1`) is more/less accurate than the formula mg(`r_2 – r_1`) for the difference of potential energy between two points `r_2` and `r_1` distance away from the centre of the

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Suppose there existed a planet that went around the sun twice as fast as the earth. What would be its orbital size as compared to that of the earth

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Io, one of the satellites of Jupiter, has an orbital period of 1.769 days and the radius of the orbit is `4.22 × 10^8` m. Show that the mass of Jupiter is about one-thousandth that of the

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Let us assume that our galaxy consists of `2.5 × 10^(11)` stars each of one solar mass. How long will a star at a distance of 50,000 ly from the galactic centre take to complete one revolution ? Take the diameter of the Milky Way to be `10^5`

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Choose the correct alternative: (a) If the zero of potential energy is at infinity, the total energy of an orbiting satellite is negative of its kinetic/potential energy. (b) The energy required to launch an orbiting satellite out of earth’s gravitational influence is more/less than the energy required to project a stationary object at the same height (as the satellite) out of earth’s

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Does the escape speed of a body from the earth depend on (a) the mass of the body, (b) the location from where it is projected, (c) the direction of projection, (d) the height of the location from where the body is

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

A comet orbits the sun in a highly elliptical orbit. Does the comet have a constant (a) linear speed, (b) angular speed, (c) angular momentum, (d) kinetic energy, (e) potential energy, (f) total energy throughout its orbit? Neglect any mass loss of the comet when it comes very close to the

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

Which of the following symptoms is likely to afflict an astronaut in space (a) swollen feet, (b) swollen face, (c) headache, (d) orientational

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

In the following two exercises, choose the correct answer from among the given ones: The gravitational intensity at the centre of a hemispherical shell of uniform mass density has the direction indicated by the arrow (see Fig 8.12) (i) a, (ii) b, (iii) c, (iv) 0.

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

For the above problem, the direction of the gravitational intensity at an arbitrary point P is indicated by the arrow (i) d, (ii) e, (iii) f, (iv)

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

0 votes

0 answers

A rocket is fired from the earth towards the sun. At what distance from the earth’s centre is the gravitational force on the rocket zero ? Mass of the sun = `2×10^(30)` kg, mass of the earth = `6×10^(24)` kg. Neglect the effect of other planets etc. (orbital radius = `1.5 × 10^(11)`

asked Mar 19, 2022 in 11th Physics by varun (6.7k points)

Recent questions in Physics

Categories