<h3><u>Answer and explanation;</u></h3>
- <u>Melting point</u> is defined as the temperature at which solid and liquid phases are in equilibrium. It is the temperature at which a solid changes state from solid to liquid at atmospheric pressure.
- <u>Boiling poin</u>t is the temperature at which the vapour pressure of a liquid is equal to the external pressure. It is the temperature at which a substance changes from a liquid into a gas.
- <u>The flash point </u>of a flammable liquid or volatile liquid is the lowest temperature at which it can form an ignitable mixture in air. At this temperature the vapor may cease to burn when the source of ignition is removed.
Answer:
The ratio is KE : TM = 0.75
Explanation:
from the question we are told that
The displacement of a mass on a spring in simple harmonic motion is A/2 from the equilibrium position
Generally the total mechanical energy of the mass is mathematically represented as

Here k is the spring constant , A is the total displacement of the the mass from maximum compression to maximum extension of the spring
Generally this total mechanical energy is mathematically represented as

=> 
Here the potential energy of the mass is mathematically represented as
![PE = \frac{1}{ 2} * k * [ x ]^2](https://tex.z-dn.net/?f=PE%20%20%20%3D%20%5Cfrac%7B1%7D%7B%202%7D%20%20%2A%20%20k%20%2A%20%20%5B%20x%20%5D%5E2)
Here x is the displacement of the mass from maximum compression or extension of the spring to equilibrium position and the value is

So
![PE = \frac{1}{ 2} * k * [ \frac{A}{2} ]^2](https://tex.z-dn.net/?f=PE%20%20%20%3D%20%5Cfrac%7B1%7D%7B%202%7D%20%20%2A%20%20k%20%2A%20%20%5B%20%5Cfrac%7BA%7D%7B2%7D%20%20%5D%5E2)
So
![KE = \frac{1}{2} * k * A^2 - \frac{1}{2} * k * [\frac{A}{2} ]^2](https://tex.z-dn.net/?f=KE%20%3D%20%20%5Cfrac%7B1%7D%7B2%7D%20%20%2A%20%20k%20%20%2A%20%20A%5E2%20-%20%5Cfrac%7B1%7D%7B2%7D%20%20%2A%20%20k%20%20%2A%20%20%5B%5Cfrac%7BA%7D%7B2%7D%20%5D%5E2)
=> 
=> 
So the ratio of
is mathematically represented as

=>
Answer:
Explanation:
a ) work done by gravitational force
= mg sinθ ( d + .21)
Potential energy stored in compressed spring
= 1/2 k x²
= .5 x 431 x ( .21 )²
= 9.5
According to conservation of energy
mg sinθ ( d + .21) = 9.5
3.2 x 9.8 x sin 30( d + .21 ) = 9.5
d = 40 cm
b )
As long as mg sin30 is greater than kx ( restoring force ) , there will be acceleration in the block.
mg sin30 = kx
3.2 x 9.8 x .5 = 431 x
x = 3.63 cm
When there is compression of 3.63 cm in the spring , block will have maximum velocity. there after its speed will start decreasing.
-- Speed = (distance) / (time to cover the distance) = 840/2.5 = 336 m/s
-- Frequency = (speed) / (wavelength) = 336/0.70 = 480 Hz.