The umbra during a solar eclipse is smaller than during a lunar eclipse.
These choices are not "levels" of sound. They're frequencies of sound.
The lower limit of audible frequency is usually considered to be 20 Hz.
But there are some people with ears that can hear 10 Hz, and others ...
particularly the elderly ... who can't hear anything below 100 Hz.
The question is a rather poor one.
Answer:
<em>The kinetic energy increases by a factor of 9
</em>
Explanation:
<u>Kinetic Energy
</u>
It's the energy related to the speed of an object and is calculated by the formula
Let's suppose the initial speed of the mass is 
, then the kinetic energy is
Now the speed will triple, i.e. 
. The new kinetic energy is
Thus
The kinetic energy increases by a factor of 9
Let's check with numbers: 
The relation is
The new kinetic energy is nine times the initial kinetic energy.
Hey again!
Ok..
Now... The melting Point of this solid is 90°C.
Meaning That as soon as it gets to this temp... It STARTS Melting.
So at that temp... It still has some solid parts in it.
You can say its a Solid Liquid Mixture.
Additional Heat being applied at that point is not raising the temperature;rather its used in breaking the bonds in the solid. This is the Fusion stage.
After Fusion...It'd then Be a Pure Liquid with no solids in it.
So
Q'=MC∆0----- This is the heat needed to take the solid's temp from 30°c - 90°c
Q"=ml ----- This is the heat used in breaking the bonds holding the solids in the solid-liquid phase.
So
Q= Q' + Q"
Q= mc∆0 + ml
∆0 = 90°c - 30°c = 60°c
Q= 2.5(390)(60) + (2.5)(4000)
Q=6.9 x 10⁴Joules
