5. The mass of cobalt-60 in a sample is found to have decreased from 0.800g to 0.200g in a
1 answer:
You might be interested in
Answer:
The speed of an electron is 0.01908 m/s.
Explanation:
De-Broglie wavelength is given by:
where, = wavelength of a particle
h = Planck's constant =
m = mass of particle
v = velocity of the particle
Velocity of an electron = v
Mass of an electron =
Wavelength of electron is twice the displacement in seconds which is velocity of an electron.
Then.wavelength of an electron =
v = 0.01908 m/s
The speed of an electron is 0.01908 m/s.
This is an incomplete question, here is a complete question.
Distinguish between Accuracy and Precision Question Jamie is measuring the mass of one mole of carbon. She measures the mass 4 times, achieving the following measurements: 11.86 g, 11.87 g, 11.89 g, and 11.90 g. If the accepted value of one mole of carbon is 12.11 g, how can Jamie's measurements best be described?
Select the correct answer below:
Jamie's measurements are both precise and accurate,
Jamie's measurements are accurate but not precise.
Jamie's measurements are precise but not accurate,
Jamie's measurements are neither precise nor accurate,
Answer : The correct option is, Jamie's measurements are precise but not accurate.
Explanation :
Accuracy : It is defined as the closeness of a measured value to a standard or known value.
For Example: If the mass of a substance is 50 kg and one person weighed 48 kg and another person weighed 55 kg. Then, the weight measured by first person is more accurate.
Precision : It is defined as the closeness of two or more measurements to each other.
For Example: If you weigh a given substance five times and you get 1.8 kg each time. Then the measurement is said to be precise.
Level of precision is determined by the maximum number of decimal places.
As we are given that:
The measurements are, 11.86, 11.87, 11.89 and 11.90
The accepted value is, 12.11
The average of these values =
From this we conclude that, these measurements are close to each other that means they are precise. But the accepted value are not equal to average of four values that means they are not accurate.
Hence, the correct option is, Jamie's measurements are precise but not accurate.