Mass spectrometer A mass spectrometer is a tool used to determine accurately the mass of individual ionized atoms or molecules,
or to separate atoms or molecules that have similar but slightly different masses. For example, you can deduce the age of a small sample of cloth from an ancient tomb, by using a mass spectrometer to determine the relative abundances of carbon-14 (whose nucleus contains 6 protons and 8 neutrons) and carbon-12 (the most common isotope, whose nucleus contains 6 protons and 6 neutrons). In organic material, the ratio of 14C to 12C depends on how old the material is, which is the basis for "carbon-14 dating." 14C is continually produced in the upper atmosphere by nuclear reactions caused by "cosmic rays" (high-energy charged particles from outer space, mainly protons), and 14C is radioactive with a half-life of 5700 years. When a cotton plant is growing, some of the CO2 it extracts from the air to build tissue contains 14C which has diffused down from the upper atmosphere. But after the cotton has been harvested there is no further intake of 14C from the air, and the cosmic rays that create 14C in the upper atmosphere can't penetrate the atmosphere and reach the cloth. So the amount of 14C in cotton cloth continually decreases with time, while the amount of non-radioactive 12C remains constant.
Carbon from the sample is ionized in the ion source at the left. The resulting singly ionized 12C+ and 14C+ ions have negligibly small initial velocities (and can be considered to be at rest). They are accelerated through the potential difference ΔV1. They then enter a region where the magnetic field has a fixed magnitude B = 0.19 T. The ions pass through electric deflection plates that are 1 cm apart and have a potential difference ΔV2 that is adjusted so that the electric deflection and the magnetic deflection cancel each other for a particular isotope: one isotope goes straight through, and the other isotope is deflected and misses the entrance to the next section of the spectrometer. The distance from the entrance to the fixed ion detector is a distance of w = 25 cm. There are controls that let you vary the accelerating potential ΔV1 and the deflection potential ΔV2 in order that only 12C+ or 14C+ ions go all the way through the system and reach the detector. You count each kind of ion for fixed times and thus determine the relative abundances. The various deflections ensure that you count only the desired type of ion for a particular setting of the two voltages.
Determine the appropriate numerical values of ΔV1 and ΔV2 for 12C. Carry out your intermediate calculations algebraically, so that you can use the algebraic results in the next part.
ΔV1 = 4 V
ΔV2 = 5 V
Determine the appropriate numerical values of ΔV1 and ΔV2 for 14C.
ΔV1 = 6 V
ΔV2 = 7 V
Carbon from the sample is ionized in the ion source at the left. The resulting singly ionized 12C+ and 14C+ ions have negligibly small initial velocities (and can be considered to be at rest). They are accelerated through the potential difference ΔV1. They then enter a region where the magnetic field has a fixed magnitude B = 0.19 T. The ions pass through electric deflection plates that are 1 cm apart and have a potential difference ΔV2 that is adjusted so that the electric deflection and the magnetic deflection cancel each other for a particular isotope: one isotope goes straight through, and the other isotope is deflected and misses the entrance to the next section of the spectrometer. The distance from the entrance to the fixed ion detector is a distance of w = 25 cm. There are controls that let you vary the accelerating potential ΔV1 and the deflection potential ΔV2 in order that only 12C+ or 14C+ ions go all the way through the system and reach the detector. You count each kind of ion for fixed times and thus determine the relative abundances. The various deflections ensure that you count only the desired type of ion for a particular setting of the two voltages.
Determine the appropriate numerical values of ΔV1 and ΔV2 for 12C. Carry out your intermediate calculations algebraically, so that you can use the algebraic results in the next part.
ΔV1 = 4 V
ΔV2 = 5 V
Determine the appropriate numerical values of ΔV1 and ΔV2 for 14C.
ΔV1 = 6 V
ΔV2 = 7 V
1 answer:
Answer:
For carbon 12
ΔV1 = 2265.31 V
ΔV2 = 362.5 V
For carbon 14
ΔV1 = 1941.7 V
ΔV2 = 310.67 V
Explanation:
The complete explanations are given in the attachment below. The formulae for the accelerating potential ΔV1 and ΔV2 are derived and the necessary parameters are substituted into the derived equations.
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The initial potential energy of the wagon containing gold boxes will enable
it roll down the hill when cut loose.
The Lone Ranger and Tonto have approximately <u>5.1 seconds</u>.
Reasons:
Mass wagon and gold = 166 kg
Location of the wagon = 77 meters up the hill
Slope of the hill = 8°
Location of the rangers = 41 meters from the canyon
Mass of Lone Ranger, m₁ = 65 kg
Mass of Tonto m₂ = 66 kg
Solution;
Height of the wagon above the level ground, h = 77 m × sin(8°) ≈ 10.72 m
Potential energy = m·g·h
Where;
g = Acceleration due to gravity ≈ 9.81 m/s²
Potential energy of wagon, P.E. ≈ 166 × 9.81 × 10.72 = 17457.0912
Potential energy of wagon, P.E. ≈ 17457.0912 J
By energy conservation, P.E. = K.E.
Where;
v = The velocity of the wagon a the bottom of the cliff
Therefore;
Velocity of the wagon, v ≈ 14.5 m/s
Momentum = Mass, m × Velocity, v
Initial momentum of wagon = m·v
Final momentum of wagon and ranger = (m + m₁ + m₂)·v'
By conservation of momentum, we have;
m·v = (m + m₁ + m₂)·v'
Which gives;
The velocity of the wagon after the Ranger and Tonto drop in, v' ≈ 8.1 m/s
The Lone Range and Tonto have approximately <u>5.1 seconds</u> to grab the
gold and jump out of the wagon before the wagon heads over the cliff.
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