Sound waves move through molecules. When there are no molecules in a certain space, sound cannot travel - whether in a vacuum or in space.
Answer:
(D) None
Explanation:
The force of gravity is the force pulling every element of matter together. The more the matter the higher the force of gravity.
Examples of this force at work are;
- The force that causes an apple to fall from the tree
- The force that causes a rock to roll downside a hill
- The force causing people to walk on the earth surface instead of floating
The force that facilitates a pen on your hand to write on a paper is friction force between the pen and the paper. Gravitational force acts downwards thus force applied on an object beside you is not the force of gravity.
72km/hr = 72000m/3600seconds(we convert km/hr to m/s
= 20m/s
Velocity= 20m/s
In 4seconds,distance covered=20x4= 80m
Therefore,an accident occurs because in 4seconds, the car would have moved past 20m
Answer:
option A is the correct answer
Answer:
Average accelation = -4V
Explanation:

V=0 m/s (because the frog stopped)
V0 = V (average velocity)
t= 0,25 s
So;
