Density = mass/volume
density = 81 grams/0.9 cubic centimetersdensity = 90 grams per cubic centimeter
The density of the sample is 90 grams per cubic centimeter.
Answer:
Height and mass
Explanation:
The potential energy of a body is the energy due to the position of a body.
It is mathematically expressed as:
Potential energy = m g h
m is the mass of the body
g is the acceleration due to gravity
h is the height of the body
Acceleration due to gravity on the earth surface is a constant.
As mass and height of a body increases, the acceleration due to gravity will also increase.
When we can get the Kinetic energy from this formula KE= 1/2 M V^2
and we can get the potential energy from this formula PE = M g H
we can set that the kinetic energy at the bottom of the fall equals the potential energy at the top so,
KE = PE
1/2 MV^2 = M g H
1/2 V^2 = g H
when V is the velocity, g is an acceleration of gravitational force and H is the height of the fall.
∴ v^2 = 2 * 9.8 * 8 = 156.8
∴ v= √156.8 = 12.5 m/s
Answer:
4.16
Explanation:
Considering the Henderson- Hasselbalch equation for the calculation of the pH of the buffer solution as:
pH=pKa+log[base]/[acid]
Where Ka is the dissociation constant of the acid.
Given that:
pKa = 3.86
Given, concentration of acid = [acid] = 0.4 M
concentration of base = [base] = 0.8 M
So,
pH=3.86+log(0.8/0.4) = 4.16
