If the density of earth is doubled keeping its radius constant then acceleration

If the density of earth is doubled keeping its radius constant then acceleration due to gravity will be (g=9.8 m/s²)

Options

(a) 19.6 m/s²
(b) 9.8 m/s²
(c) 4.9 m/s²
(d) 2.45 m/s²

Correct Answer:

19.6 m/s²

Explanation:

Acceleration due to gravity g=GM/R² ——-(1)
The radius is constant, volume also constant.
If volume is constant, density is proportional to mass.(v=m/ρ)
The density is doubled, the mass is also doubled. (M’=2M)
The new acceleration due to gravity g’=GM’/R’²
Put the value M’=2M and R’=R
g’=G(2M)/R²
g’=2GM/R² ——–(2)
Substituting equations (1) and (2), we get
g’=2g
g=9.8 m/s²
g’=2×9.8=19.6 m/s²

admin:

Related Questions

  1. In photoelectric effect, the photoelectric current
  2. In the given figure, a diode D is connected to an external resistance R=100 Ω
  3. In producing chlorine through electrolysis 100 watt power at 1125 V is being
  4. In which of the following heat loss is primarily not due to convection?
  5. Radius of orbit of satellite of earth is R. Its kinetic energy is proportional to