Answer : (C) "Higher frequencies have larger spaces between lines".
Explanation:
In Young's experiment, the condition for constructive interference is given by :
.........(1)
n is order or number of lines observed
d is distance between slits
is the angle between the path and the line from screen to the slits.
We also know that, 
or
where,
c is the speed of light
is frequency
is wavelength
So, equation (1) turns into
So,
or
Higher frequencies have larger spaces between line.
So, correct option is (C).
Answer: The final temperature of nickel and water is 
.
Explanation:
The given data is as follows.
Mass of water, m = 55.0 g,
Initial temp, 
,
Final temp, 
= ?,
Specific heat of water = 4.184 
,
Now, we will calculate the heat energy as follows.
q = 
= 
Also,
mass of Ni, m = 15.0 g,
Initial temperature, 
,
Final temperature, 
= ?
Specific heat of nickel = 0.444
Hence, we will calculate the heat energy as follows.
q =
= 
Therefore, heat energy lost by the alloy is equal to the heat energy gained by the water.
= -()
=
Thus, we can conclude that the final temperature of nickel and water is .
Answer:
A) An ionic bond is much stronger than most covalent bonds.
Explanation:
D) Ionic compounds have high melting points causing them to be solid at room temperature, and conduct electricity when dissolved in water. Covalent compounds have low melting points and many are liquids or gases at room temperature.
C) An ionic bond is a type of chemical bond formed through an electrostatic attraction between two oppositely charged ions. Ionic bonds are formed between a cation, which is usually a metal, and an anion, which is usually a nonmetal. A covalent bond involves a pair of electrons being shared between atoms.
A) Covalent bonds are stronger if you compare with ionic molecules, because their molecular orbital overlap is bigger. However, ionic molecules form lattices, thus the energy to break this lattice bond is stronger hence the ionic bond is stronger.
Answer: Europe
Explanation: it’s in germany
