Answer:
Lightning is a process that occurs when the positive and negative charges present in the cloud build up in such a manner that a spark of lightning occurs between the two of them in the cloud. ... A metal rod placed on top of a building to protect it from a lightning strike is known as a lightning conductor.
Explanation:
<h2>
Answer: an underground lake</h2>
Explanation:
In general, sound (mechanical waves) travels faster in solids than in liquids, and faster in liquids than in gases. This is because <u>the speed of the mechanical waves is determined by a relationship between the elastic properties of the medium </u>in which they are propagated and the mass per unit volume of the medium (that is:<u>density</u>).
In other words: The speed of sound varies depending on the medium through which the sound waves travel.
So, if we are told the sound wave initially had a speed of 4,000 m/s and it suddenly decreases to 1,500 m/s, this means the sound waves passed from a solid medium to a liquid medium.
Hence, the correct option is: an underground lake.
Answer:16.096
Explanation:
Given
mass of dog
mass of boat
distance moved by dog relative to ground=
distance moved by boat relative to ground=
Distance moved by dog relative to boat=7.8m
There no net force on the system therefore centre of mass of system remains at its position
0=
0=

i.e. boat will move opposite to the direction of dog
Now

substituting
value



now the dog is 22.5-6.403=16.096m from shore