The mass of the planet Gallifrey is 8 times the mass of the Earth.
- let the gravitational field of Earth = g
- let the radius of the Earth = R
- gravitational field of Gallifrey = 2g
- radius of Gallifrey = 2R
<h3>What is gravitational potential energy?</h3>
- This is the work done in moving an object to a certain distance against gravitational field.
The gravitational field strength of the Earth is given as follows;
![g = \frac{GM}{r^2} \\\\G = \frac{gr^2}{M}](https://tex.z-dn.net/?f=g%20%3D%20%5Cfrac%7BGM%7D%7Br%5E2%7D%20%5C%5C%5C%5CG%20%3D%20%5Cfrac%7Bgr%5E2%7D%7BM%7D)
The gravitational field strength of the Planet Gallifrey is calculated as follows;
![g_2 = \frac{GM_2}{r_2^2}](https://tex.z-dn.net/?f=g_2%20%3D%20%5Cfrac%7BGM_2%7D%7Br_2%5E2%7D)
![G = \frac{g_2r_2^2}{M_2} \\\\\frac{g_2r_2^2}{M_2} = \frac{gr^2}{M}\\\\M_2gr^2 = Mg_2r_2^2\\\\M_2 = \frac{Mg_2r_2^2}{gr^2} \\\\M_2 = \frac{M \times 2g \times (2r)^2}{gr^2} \\\\M_2 = \frac{M \times 2g \times 4r^2}{gr^2} \\\\M_2 = 8M](https://tex.z-dn.net/?f=G%20%3D%20%5Cfrac%7Bg_2r_2%5E2%7D%7BM_2%7D%20%5C%5C%5C%5C%5Cfrac%7Bg_2r_2%5E2%7D%7BM_2%7D%20%3D%20%5Cfrac%7Bgr%5E2%7D%7BM%7D%5C%5C%5C%5CM_2gr%5E2%20%3D%20Mg_2r_2%5E2%5C%5C%5C%5CM_2%20%3D%20%5Cfrac%7BMg_2r_2%5E2%7D%7Bgr%5E2%7D%20%5C%5C%5C%5CM_2%20%3D%20%5Cfrac%7BM%20%5Ctimes%202g%20%5Ctimes%20%282r%29%5E2%7D%7Bgr%5E2%7D%20%5C%5C%5C%5CM_2%20%3D%20%5Cfrac%7BM%20%5Ctimes%202g%20%5Ctimes%204r%5E2%7D%7Bgr%5E2%7D%20%5C%5C%5C%5CM_2%20%3D%208M)
Thus, the mass of the planet Gallifrey is 8 times the mass of the Earth.
Learn more about gravitational field strength here: brainly.com/question/14080810
The answer is Density. The Density of the <span>glass is measured with bromoform and bromobenzene mixtures in a column. </span>Density measurement<span> is done using Density gradient </span>columns. It is a <span> temperature-controlled density </span>column<span> containing a </span>mixture<span> of b</span>romobenzene<span> and </span>bromoform.
The horizontal force : f = k*N
k- coefficient of friction
k = f /N
N = m * g = 45 kg * 9.81 m/s² = 441.45 N
k = 25 N : 441.45 N = 0.057
Answer C) 0.057