Answer:
Explanation:
mass of elephant, m1 = 5240 kg
mass of ball, m2 = 0.150 kg
initial velocity of elephant, u1 = - 4.55 m/s
initial velocity of ball, u2 = 7.81 m/s
Let the final velocity of ball is v2.
Use the formula of collision


v2 = - 16.9 m/s
The negative sign shows that the ball bounces back towards you.
(b) It is clear that the velocity of ball increases and hence the kinetic energy of the ball increases. This gain in energy is due to the energy from elephant.
Explanation:
We start by using the conservation law of energy:

or

Simplifying the above equation, we get

We can rewrite this as

Note that the expression inside the parenthesis is simply the acceleration due to gravity
so we can write

where
is the launch velocity.
This affirmative is false
Answer:
30°
Explanation:
According to the second law of reflection, it States that the angle of incidence i is equal to the angle of reflection r.
The angle of incidence is known to be the angle between the incident ray and the normal.
The Angle of reflection is the angle between the reflected ray and the normal.
This normal ray is a ray that is perpendicular to the surface.
According to the question, if the beam of light is reflected off the surface and its angle of incidence is 30°, its angle of reflection will also be 30° i.e i=r = 30°