D. Binary Stars
Well, galaxies are not stars at all rather they are collection of stars, nebulae, globular clusters and stuff like this.
Meteoroids are something entirely different.
Constellations are the pattern of stars.
So, "Binary Stars" is the Right One.
Answer:
The mass of the object, its acceleration due to gravity and the distance between the top of the hill and the ground level.
Explanation:
gravitational potential energy is the energy possessed by a body under influence of gravitational force by virtue of its position.
In order to determine the gravitational potential energy of the brick, we must know the mass (m) of the brick, its acceleration due to gravity (g) since it is acting under the influence of gravitational force and the distance between the top of the hill and the ground level. (The height).
Potential energy of a body is calculated as mass × acceleration due to gravity × height.
Answer:
1 my brother say that
Explanation:
i know my brother said it
Answer:
a. 
b.
must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c.
is the time taken to stop after braking
Explanation:
Given:
- speed of leading car,

- speed of lagging car,

- distance between the cars,

- deceleration of the leading car after braking,

a.
Time taken by the car to stop:

where:
, final velocity after braking
time taken


b.
using the eq. of motion for the given condition:

where:
final velocity of the chasing car after braking = 0
acceleration of the chasing car after braking

must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c.
time taken by the chasing car to stop:


is the time taken to stop after braking
Because: Some of the work done by the machine is used to overcome the friction created by the use of the machine. ... Work output can never be greater than work input. Machines allow force to be applied over a greater distance, which means that less force will be needed for the same amount of work.