Answer:
weight= density ×volume× 9.8
mass=density×volume
Explanation:
Answer:
Explanation:
a) Hardness is a measure of the resistance of a material to permanent deformation (plastic) on its surface,
Hardness tests play an important role in material testing, quality control and component acceptance.
Hardness test are needed to be perform as a <em>quality assurance procedure</em>, to validate materials are according to the specific hardness required,
We depend on the data to verify the quality of the components to determine if a material has the necessary properties for its intended use.
Through the years, the establishment of increasingly productive and effective means of testing, has given way to new cutting-edge methods that perform and interpret hardness tests more effectively than ever. The result is a greater capacity and dependence on "letting the instrument do the work", contributing to substantial increases in performance and consistency and continuing to make hardness tests very useful in industrial and R&D applications.
b)
- <u>Instrumental errors</u>: Instrument calibration is extremely important. An instrument with expired calibration may be generating erroneous data systematically.
- <u>Enviromental error: </u>An example is when surface preparation of the sample to be tested is poor, then the error can be presented when measuring the indentation on the sample to determine the hardness value.
Answer:
0.544 eV
Explanation:
To ionize the hydrogen atom 
So the required energy is 
as
So 
We have to calculate the energy required to ionize hydrogen atom when it is in n=5
So the energy should be less than 
Hi there!
Use the following formula to solve:
KE = 1/2mv², where:
KE = kinetic energy
m = mass (kg)
v = velocity (m/s)
Therefore:
KE = 1/2(1500)(30)²
KE = 1/2(1500)(900)
KE = 675000 J
