The statements that describes accurately about elements are :
Elements are made up of only one type of atom.
Each element has a unique chemical symbol.
Elements can be identified by their àtomic number
<u>Explanation:</u>
Simple and complete chemical substances are called elements. An element contains only one type of atom. In a periodic table each of the the element occupies unique entry respectively. The atom that is present in an element contains similar number of protons and this is said to be an atomic number. Each element is represented by an unique one or two letters in the periodic table.
One Element differs for another element by the number of protons present in the nucleus. If there is one proton in an atom it is said to be hydrogen atom and if it has two atoms then it is known to be a helium atom.Lithium refers to the atom with three protons.
Answer:
Explanation:
The intensity of a sound wave is given by
where
P is the power of the wave at the source
A is the area over which the sound wave propagates
In this problem, we have
P = 70.0 W is the power
We want to know the intensity at a distance of r = 25.0 m from the orchestra, so since the sound waves propagates radially, we must consider a spherical surface of radius r, so the area is
Therefore, the intensity of the wave is
W = Fd
W = 1225 N x 10 m = 12250
Answer:
4E
Explanation:
From the question given above, the following data were obtained:
Initial elongation (e₁) = 4 cm = 4/100 = 0.04 m
Initial energy (E₁) = E
Final elongation (e₂) = 0.04 + 0.04 = 0.08 m
Final energy (E₂) =?
The energy stored in a s spring is given by:
E = ½Ke²
Where
E => is the energy
K => is the spring constant
e => is the elongation
From:
E = ½Ke²
Energy is directly proportional to the elongation. Thus,
E₁/e₁² = E₂/e₂²
With the above formula, we can obtain the final energy as follow:
Initial elongation (e₁) = 0.04 m
Initial energy (E₁) = E
Final elongation (e₂) = 0.08 m
Final energy (E₂) =?
E₁/e₁² = E₂/e₂²
E / 0.04² = E₂ / 0.08²
E / 0.0016 = E₂ / 0.0064
Cross multiply
0.0016 × E₂ = 0.0064E
Divide both side by 0.0016
E₂ = 0.0064E / 0.0016
E₂ = 4E
Therefore, the final energy is 4 times the initial energy i.e 4E
Explanation:
This element have 10 neutrons