Answer:
Fundamental frequency in the string will be 25 Hz
Explanation:
We have given length of the string L = 1.2 m
Speed of the wave on the string v = 60 m/sec
We have to find the fundamental frequency
Fundamental frequency in the string is equal to
, here v is velocity on the string and L is the length of the string
So frequency will be equal to 
So fundamental frequency will be 25 Hz
Psychiatry assesses and treats people with mental disorders
Answer: 
Explanation:
Given
mass of ball m=10 kg
It is placed at a height of 150 m
It is dropped from the height and allowed to free fall for 40 m
Velocity acquired by the ball during this fall is given by 
Insert u=0, a=g

Kinetic energy at this instant

Answer:
~~Now, you have left your question very open ended and didn't ask for any particular kind of answer so I'll do my best to get what you're looking for.~~
A physical change in a substance doesn't change what the substance is. It can possibly melt or freeze an object. I mean heat makes things expand while cooling makes them retract.... In chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.