Forum

Why do we called lysosomes as susideble bags? 

cell cycle and cell division

What is the difference between meiosis and mitosis 

Accounts

How is goodwill calculated in partnership accounts?

Life processes

What do you mean by life processes? Explain with examples.

JEE Mains (Gravitation)

Two bodies of masses m and 4m are placed at a distance r. The gravitational potential at a point on the line joining them where the gravitational field is zero is

(a) -6Gm/r

(b) -9Gm/r

(c) Zero

(d) -4Gm/r

JEE Mains (Gravitation)

A geostationary satellite orbits around the earth in a circular orbit of radius 36,000km. Then, the time period of a spy satellite orbiting a few hundred km above the earth’s surface (R =6,400km) will approximately be

(a) (l/2)hr

(b) 1 hr

(c) 2 hr

(d) 4 hr

JEE Mains (Gravitation)

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. The value of T₂/T₁ is

(a) 1

(b) 3

(c) 4

(d) 2

JEE Mains (Gravitation)

An artificial satellite moving in a circular orbit around the earth has a total (K.E. + P.E.) energy E₀. Its potential energy is

(a) – E₀

_(b) 1.5 E₀

(c) 2 E₀

(d) E₀

JEE Mains (Gravitation)

The mass of a spaceship is 1000 kg. It is to be launched from the earth’s surface out into free space. The value of ‘g’ and ‘R’ (radius of the earth) is 10 m/s² and 6400 km respectively. The required energy for this work will be

(a) 6.4 x 10¹⁰ Joules

(b) 6.4 x 10¹¹ Joules

(c) 6.4 x 10⁸ Joules

(d) 6.4 x 10⁹ Joules

JEE Mains (Gravitation)

If the distance between the earth and the sun were half its present value, the number of days in a year would have been

(a) 64.5

(b) 129

(c) 182.5

(d) 730