<span>An imaginary line perpendicular to a reflecting surface is called "a normal" (principle line)
So, Your Answer would be Option B
Hope this helps!</span>
Answer:

Explanation:
From the question we are told that
Weight of fireman 
Pole distance 
Final speed is 
Generally the equation for velocity is mathematically represented as

Therefore Acceleration a
Generally the equation for Frictional force
is mathematically given as



Therefore

Answer:
earth
Explanation:
The formula for the orbital period of the moon is given by

As the time period is inversely proportional to the square root of the acceleration due to gravity of the planet.
As the value of acceleration due to gravity on Jupiter is more than the earth, so the period of moon around the earth is large as compared to the period of the moon around the Jupiter when the distance is same.
Answer:
K = 0.076 J
Explanation:
The height of the target, h = 0.860 m
The mass of the steel ball, m = 0.0120 kg
Distance moved, d = 1.50 m
We need to find the kinetic energy (in joules) of the target ball just after it is struck. Let t is the time taken by the ball to reach the ground.

Put all the values,

The velocity of the ball is :

The kinetic energy of the ball is :

So, the required kinetic energy is 0.076 J.
One is for far distance the other is for close range