Black holes absorb all surrounding matter and energy within a certain proximity. For this reason, these celestial objects emit no light and therefore do not have a color or black in color.Black holes are the most dense objects in the universe. Because of their density, they form extremely powerful gravitational fields.

Motion is defined as a change in position of an object over time. Motion is described in terms of displacement, distance, velocity, acceleration, time and speed.

The normal line divides the angle between the incident ray and the reflected ray into two equal angles.At the point of incidence where the ray strikes the mirror, a line can be drawn perpendicular to the surface of the mirror. This line is known as a normal line

Motion is a change in position of an object over time. Motion is described in terms of displacement, distance, velocity, acceleration, time and speed.

In physics, motion is a change in position of an object over time. Motion is described in terms of displacement, distance, velocity, acceleration, time and speed.

One newton is the force needed to accelerate one kilogram of mass at the rate of one metre per second squared in direction of the applied force.

1 newton of force is the force required to accelerate an object with a mass of 1 kilogram 1 meter per second per second.

1 N = 1 Kg {tex}m/ s^2{/tex}.

An inelastic collision, in contrast to an elastic collision, is a collision in which kinetic energy is not conserved due to the action of internal friction. In collisions of macroscopic bodies, all kinetic energy is turned into vibrational energy of the atoms, causing a heating effect, and the bodies are deformed.

In an inelastic collision kinetic energy is lost (generally through energy used to change an objects shape), but the two objects rebound off each other with the remaining kinetic energy.Momentum is conserved in inelastic collisions, but one cannot track the kinetic energy through the collision since some of it is converted to other forms of energy.

In a perfectly inelastic collision the two objects stick together after the collision.A perfectly inelastic collision occurs when the maximum amount of kinetic energy of a system is lost. In a perfectly inelastic collision, i.e., a zero coefficient of restitution, the colliding particles stick together. In such a collision, kinetic energy is lost by bonding the two bodies together.

Kinetic energy (K.E) = 1/2 mv²        

multiply and divide RHS by m, we get K.E.= m²v² /2m ........(i)

Momentum =p =mv..............(ii)

Substitute value from eq (ii) in eq(i) , we get   K.E. =p² /2m

Acceleration is the rate of change of velocity with respect to time

a= (final velocity - initial velocity) / time

SI units are m/s²