Answer:
15 protons and 18 electrons
General Formulas and Concepts:
<u>Chemistry</u>
- Reading a Periodic Table
- Element Number
- Neutral Atoms
- Ions
Explanation:
We are given the element P. P is 15 on the Periodic Table, meaning it has 15 protons and 15 electrons (all elements are in neutral form).
P³⁻ ion means the element now has a negative charge of 3. We know protons have a positive charge and electrons have a negative charge. 3- means we will have more electrons than protons.
Therefore, P³⁻ would have 15 protons and <em>18</em> electrons:
15 (+) + 18 (-) = 3 (-)
Answer:
280 N
Explanation:
acceleration = v2-v1 / time taken = (2-4 )/ 0.05 = -40 m/s^2 ( neg sign indicates slowing down )
force exerted = ma = 7 kg x -40 m/s^2 = - 280 N ( neg sign means opposite direction of initial velocity )
since the 7 kg ball is slowing down, the direction of force will be opposite of the initial velocity , and it will be 280 N
Answer:
-2.67 m/s²
Explanation:
a = Δv / Δt
a = (14 m/s − 30 m/s) / (6 s − 0 s)
a = -2.67 m/s²
Answer:
The displacement of the air drop after 3 second is 18.27 m.
Explanation:
Mass of the rain drop = m = 
Weight of the rain drop = W
Duration of time = t = 3 seconds
Drag force on rain drop = 
Motion of the rain drop:
Net force on the rain drop , F= W - D
v = 12.18 m/s
Initial velocity of the rain drop = u = 0 (since, it is starting from rest)
v=u+at (First equation of motion)
(second equation of motion)
s = 18.27 m
The displacement of the air drop after 3 second is 18.27 m.
Melting freezing and boiling are molecular changes
