Answer: A negatively-charged ion always has more electrons than protons
Explanation:
First, we know that the elementary negative charge is the electron, while the positive one is the proton. Such that both have the same charge in magnitude, but a different sign. Such that if we have the same number of electrons and protons in an atom, the charge of this atom will be neutral.
And an ion is an atom with a different number of electrons and protons, so the charge of the atom is not neutral.
Then if we have a negatively-charged ion, the charge of this atom is negative. Then we must have a larger number of electrons (the negative ones) than protons (the positive ones)
Then the correct option is:
A negatively-charged ion always has more electrons than protons
Answer: Photoreceptor cell, Chemoreceptor, Thermoreceptor, Mechanoreceptor
Hope this helps(:
Explanation:
Explanation:
The energy stored in coal is directly form the sun which is solar energy. This energy are preserved in carbon atoms and they originate from the life processes of a plant.
- Plants carry out photosynthesis and produce their energy by this process.
- Green plants have special adapted structures by which they trap solar energy from the sun and use it to produce their own food.
- The food is used by plant for nutrition and life activities.
- In essence the solar energy is converted to chemical energy in plants.
- To form coal, when plants are rapidly buried their organic matter is preserved from decay by combination with oxygen.
- More burial preserves the complex molecules that have stored during photosynthesis.
- The carbon eventually aggregates for coal.
learn more:
Coal brainly.com/question/10055728
#learnwithBrainly
Answer:
COMPLETE QUESTION
A spring stretches by 0.018 m when a 2.8-kg object is suspended from its end. How much mass should be attached to this spring so that its frequency of vibration is f = 3.0 Hz?
Explanation:
Given that,
Extension of spring
x = 0.0208m
Mass attached m = 3.39kg
Additional mass to have a frequency f
Let the additional mass be m
Using Hooke's law
F= kx
Where F = W = mg = 3.39 ×9.81
F = 33.26N
Then,
F = kx
k = F/x
k = 33.26/0.0208
k = 1598.84 N/m
The frequency is given as
f = ½π√k/m
Make m subject of formula
f² = ¼π² •(k/m
4π²f² = k/m
Then, m4π²f² = k
So, m = k/(4π²f²)
So, this is the general formula,
Then let use the frequency above
f = 3Hz
m = 1598.84/(4×π²×3²)
m = 4.5 kg
