Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Gravitation question

2023 · 10 Apr · Shift 1 · Q63
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Physics
  4. /Gravitation
  5. /2023 · 10 Apr · Shift 1 · Q63

Gravitation question

2023 · 10 Apr · Shift 1 · Q63

JEE MainPhysicsGravitationMCQ+4 / −1
Assuming the earth to be a sphere of uniform mass density, the weight of a body at a depth d=R2d=\frac{R}{2}d=2R​ from the surface of earth, if its weight on the surface of earth is 200 N, will be: (Given R = radius of earth)
  1. A
    100 N
  2. B
    400 N
  3. C
    300 N
  4. D
    500 N
View written solutionFree

Correct answer: A

  1. Given:

    • Earth is assumed to be a sphere of uniform density.
    • Weight on the surface: W=200 NW = 200\,\text{N}W=200N
    • Depth from surface: d=R2d = \dfrac{R}{2}d=2R​
  2. **Formula for acceleration due to gravity at depth ddd: ** For a uniform spherical earth, gd=g(1−dR)g_d = g\left(1 - \frac{d}{R}\right)gd​=g(1−Rd​)

  3. Substitute d=R2d = \dfrac{R}{2}d=2R​: gd=g(1−R/2R)=g(1−12)=g2g_d = g\left(1 - \frac{R/2}{R}\right) = g\left(1 - \frac{1}{2}\right) = \frac{g}{2}gd​=g(1−RR/2​)=g(1−21​)=2g​

  4. **Weight is proportional to ggg: ** Wd=W⋅gdgW_d = W\cdot \frac{g_d}{g}Wd​=W⋅ggd​​ Wd=200×12=100 NW_d = 200 \times \frac{1}{2} = 100\,\text{N}Wd​=200×21​=100N

  5. Check options:

    • A: 100 N100\,\text{N}100N ✅
    • B: 400 N400\,\text{N}400N ❌
    • C: 300 N300\,\text{N}300N ❌
    • D: 500 N500\,\text{N}500N ❌

Therefore, the correct answer is A.

PreviousNext

More from Gravitation

  • If the earth suddenly shrinks to 641​ th of its original volume with its mass remaining the same, the period of rotation of earth becomes x24​ h. The value of x is ​.2023 · Numerical
  • The time period of a satellite, revolving above earth's surface at a height equal to R will be (Given g=π2 m/s2,R= radius of earth)2023 · MCQ
  • Given below are two statements: Statement I : Rotation of the earth shows effect on the value of acceleration due to gravity (g) Statement II : The effect of rotation of the earth on the value of 'g' at the equator is minimum and that at…2023 · MCQ
  • The radii of two planets 'A' and 'B' are 'R' and '4R' and their densities are ρ and ρ/3 respectively. The ratio of acceleration due to gravity at their surfaces (gA​:gB​) will be:2023 · MCQ
  • A space ship of mass 2×104 kg is launched into a circular orbit close to the earth surface. The additional velocity to be imparted to the space ship in the orbit to overcome the gravitational pull will be (if g=10 m/s2…2023 · MCQ
  • If V is the gravitational potential due to sphere of uniform density on it's surface, then it's value at the center of sphere will be:-2023 · MCQ
  • The ratio of escape velocity of a planet to the escape velocity of earth will be:- Given: Mass of the planet is 16 times mass of earth and radius of the planet is 4 times the radius of earth.2023 · MCQ
  • Two satellites A and B move round the earth in the same orbit. The mass of A is twice the mass of B. The quantity which is same for the two satellites will be2023 · MCQ