Answer:
A. Atoms are the smallest unit of an element.
Explanation:
The correct statement from the given choices is that atoms are the smallest unit of an element.
Atoms are the smallest particles that takes part in chemical reactions and they are made up of protons, neutrons and electrons.
- Elements are distinct substances that cannot be split up into simpler substances.
- They are made up of only one kind of atoms.
- Elements are not changed into atoms by chemical reactions.
- In chemical reactions, atoms simply recombine.
Answer:
1.308 * 10^(-5) m
Explanation:
We apply the condition for a single slit experiment:
y = (λ * D) / a
Where y = half width of fringe
λ = wavelength of light
D = distance of slit from screen
a = width of slit
We need to find a, so we make a the subject of formula:
a = (λ * D) / y
From the question:
λ = 550 nm = 550 * 10^(-9) m
D = 0.63 m
y = 0.053 / 2 = 0.0265 m
Therefore:
a = (550 * 10^(-9) * 0.63) / 0.0265
a = 1.308 * 10^(-5) m
The width of the slit is 1.308 * 10^(-5) m
Answer:

Explanation:
We are given that
Distance between plates=d=2.2 cm=


Using 
We have to find the magnitude of E in the region between the plates.
We know that the electric field for parallel plates





Where 
Substitute the values


Hence, the magnitude of E in the region between the plates=
Answer:
the answer is A.
Explanation:
An atom contains equal numbers of protons and electrons . Since protons and electrons have equal and opposite charges , this means that atoms are neutral overall.
All liquids become solid, above the melting point!!! Hope this helps!!!