Answer:
An element is a pure substance and is made of only one type of atom.
Explanation:
It cannot be broken down into a simpler substance.
Hi there!
We can use Newton's Second Law:

ΣF = Net force (N)
m = mass (kg)
a = acceleration (m/s²)
We can rearrange the equation to solve for the acceleration.

Answer:
Part a)

Part b)


Part c)


Explanation:
Part a)
frequency of light will not change with change in medium but it will depend on the source only
so here frequency of light will remain same in both water and glass and it will be same as that in air



Part b)
As we know that the refractive index of water is given as

so the wavelength in the water medium is given as



Similarly the refractive index of glass is given as

so the wavelength in the glass medium is given as



Part c)
Speed of the wave in water is given as



Speed of the wave in glass is given as



Answer:
The change in temperature is
Explanation:
From the question we are told that
The temperature coefficient is 
The resistance of the filament is mathematically represented as
![R = R_o [1 + \alpha \Delta T]](https://tex.z-dn.net/?f=R%20%20%3D%20%20R_o%20%5B1%20%2B%20%5Calpha%20%20%5CDelta%20T%5D)
Where
is the initial resistance
Making the change in temperature the subject of the formula
![\Delta T = \frac{1}{\alpha } [\frac{R}{R_o} - 1 ]](https://tex.z-dn.net/?f=%5CDelta%20T%20%3D%20%5Cfrac%7B1%7D%7B%5Calpha%20%7D%20%5B%5Cfrac%7BR%7D%7BR_o%7D%20-%201%20%5D)
Now from ohm law

This implies that current varies inversely with current so

Substituting this we have
![\Delta T = \frac{1}{\alpha } [\frac{I_o}{I} - 1 ]](https://tex.z-dn.net/?f=%5CDelta%20T%20%20%3D%20%5Cfrac%7B1%7D%7B%5Calpha%20%7D%20%5B%5Cfrac%7BI_o%7D%7BI%7D%20-%201%20%5D)
From the question we are told that

Substituting this we have
![\Delta T = \frac{1}{\alpha } [\frac{I_o}{\frac{I_o}{8} } - 1 ]](https://tex.z-dn.net/?f=%5CDelta%20T%20%20%3D%20%5Cfrac%7B1%7D%7B%5Calpha%20%7D%20%5B%5Cfrac%7BI_o%7D%7B%5Cfrac%7BI_o%7D%7B8%7D%20%7D%20-%201%20%5D)
=> 
Answer:
It will be A. So since its 2 times more the kinetic energy. But then you have to square it 2^2 = 4