The neutral lambda particle Λ0 is a baryon with a strangeness of −1
1.
One possible decay for a Λ0 is
Λ0 → π 0 + n
(a) Deduce the quark structure of a Λ0.
___________________________________________________________________
(1)
(b) State and explain which interaction is involved in this decay.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(2)
(c) An antiparticle of the neutral lambda particle decays into a neutral pion and particle X.
Identify X.
___________________________________________________________________
(1)
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, (d) The rest energy of a Λ0 is equal to the energy of a photon with a frequency of 2.69 × 1023
Hz.
Determine, in MeV, the rest energy of a Λ0.
rest energy = ____________________ MeV
(1)
(e) The discovery of particles such as the Λ0 is made by large international research teams.
Suggest one reason for this.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(1)
(Total 6 marks)
In 2021 the world land speed record was 1230 km h−1.
2.
This was the average speed achieved by a jet-powered car in two runs. Each run was measured
over a distance of 1.61 km.
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,(a) The average speed for one of these runs was 343 m s−1.
Calculate, in s, the time taken for the car to complete the other run.
time = ____________________ s
(2)
(b) Engineers are designing a new jet-powered car to break this record.
Figure 1 shows the variation of speed with distance for the car, as predicted by the
engineers.
Figure 1
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, The car reaches its maximum acceleration when it is 5600 m from the start. At this point
the mass of the car is 6.50 × 103 kg.
Determine the kinetic energy of the car at its maximum acceleration.
kinetic energy = ____________________ J
(2)
(c) At any point on the graph in Figure 1, the acceleration is given by:
acceleration = speed × gradient of line
When the car is at its maximum acceleration, the power input to the jet engines is 640 MW.
Calculate the percentage of the input power used to accelerate the car at its maximum
acceleration.
percentage of input power = ____________________ %
(4)
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1.
One possible decay for a Λ0 is
Λ0 → π 0 + n
(a) Deduce the quark structure of a Λ0.
___________________________________________________________________
(1)
(b) State and explain which interaction is involved in this decay.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(2)
(c) An antiparticle of the neutral lambda particle decays into a neutral pion and particle X.
Identify X.
___________________________________________________________________
(1)
Hartland International School Page 1 of 44
, (d) The rest energy of a Λ0 is equal to the energy of a photon with a frequency of 2.69 × 1023
Hz.
Determine, in MeV, the rest energy of a Λ0.
rest energy = ____________________ MeV
(1)
(e) The discovery of particles such as the Λ0 is made by large international research teams.
Suggest one reason for this.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(1)
(Total 6 marks)
In 2021 the world land speed record was 1230 km h−1.
2.
This was the average speed achieved by a jet-powered car in two runs. Each run was measured
over a distance of 1.61 km.
Hartland International School Page 2 of 44
,(a) The average speed for one of these runs was 343 m s−1.
Calculate, in s, the time taken for the car to complete the other run.
time = ____________________ s
(2)
(b) Engineers are designing a new jet-powered car to break this record.
Figure 1 shows the variation of speed with distance for the car, as predicted by the
engineers.
Figure 1
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, The car reaches its maximum acceleration when it is 5600 m from the start. At this point
the mass of the car is 6.50 × 103 kg.
Determine the kinetic energy of the car at its maximum acceleration.
kinetic energy = ____________________ J
(2)
(c) At any point on the graph in Figure 1, the acceleration is given by:
acceleration = speed × gradient of line
When the car is at its maximum acceleration, the power input to the jet engines is 640 MW.
Calculate the percentage of the input power used to accelerate the car at its maximum
acceleration.
percentage of input power = ____________________ %
(4)
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