Question

Still considering the system of the comet plus the star, which of the following statements are correct? A. The sum of the kinetic energy of the system plus the gravitational potential energy of the system is a positive number. B. Along this path the gravitational potential energy of the system is never zero. C. The gravitational potential energy of the system is inversely proportional to the square of the distance between the comet and star. D. At every location along the comet's path the gravitational potential energy of the system is negative. E. The sum of the kinetic energy of the system plus the gravitational potential energy of the system is the same at every location along this path.

Answer 1

Answer:

B. Along this path the gravitational potential energy of the system is never zero.

D. At every location along the comet's path the gravitational potential energy of the system is negative.

E. The sum of the kinetic energy of the system plus the gravitational potential energy of the system is the same at every location along this path.

Explanation:

Gravitational potential energy of the system is given as

$U = -\frac{Gm_1m_2}{r}$

now we know that

$KE = \frac{1}{2}mv^2$

since the system is bounded to move together so the total mechanical energy must be negative

so sum of kinetic energy and potential energy must be negative at all locations.

Also we know that that potential energy is always non zero and a negative quantity here.