Calculation of the gravitational force. 1. What is the gravitational force (in N) on a proton at the surface of the Sun? 2. At a point mid way to the surface? The average density ρ of the Universe today is 3 × 10−27kgm−3 Find this density in (a) gcm^−3 (b) M⊙Mpc^−3 (c) mpcm^−3 2. Find the mass within a sphere
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Calculation of the gravitational force.
1. What is the gravitational force (in N) on a proton at the surface of the Sun?
2. At a point mid way to the surface?
The average density ρ of the Universe today is 3 × 10−27kgm−3
Find this density in (a) gcm^−3
(b) M⊙Mpc^−3
(c) mpcm^−3
2. Find the mass within a sphere of radius (a) R⊙ (b) 1 AU (c) 10 Mp
1. The gravitational force on a proton at the surface of the Sun is 6.67 x 10-11 N.
2. The gravitational force on a proton at a point midway to the surface of the Sun is 3.33 x 10-11 N.
1. (a) The average density of the Universe today is 3 x 10-27 kgm-3.
(b) The average density of the Universe today is 3 x 10-27 M. Mpe-3.
(c) The average density of the Universe today is 3 x 10-27 mpcm-3.
2. (a) The mass within a sphere of radius Ro is 2.42 x 1030 kg.
(b) The mass within a sphere of radius 1 AU is 1.99 x 1030 kg.
(c) The mass within a sphere of radius 10 Mpe is 3.11 x 1040 kg.
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