Edexcel P2 - 12/06/2014 - 'Unofficial Markscheme'

Post the questions. I can't remember them all.

Question - Half life:
Half life period - 5.4 years.
8000bq -> 1000bq = 16.2 years.

Question: Acceleration equation:
Acceleration = Change in velocity/Time taken
1.2 = 7/x
7/1.2 = 5.833333.

Question: Isotopes:
The two isotopes have the same number of electrons and protons but differing number of neutrons. Can't remember exact values.

Question: Father and wheelbarrow question:
450/1.5 = 300N.

Question: Work, power:
a) Power
b) The work done is equivalent to the energy transferred.

Question: Direction of forces - car and truck:
Answer - B in the table (---> <---)

Question - Why don't neutrons have to be slowed in Fusion?:
Answer - Fusion involves no absorption of neutrons... so why would they need to be slowed.

Question - Conditions for fusion & why those conditions are needed:
Very high temperature (millions of degrees C) and pressure or magnetic confinement to overcome electrostatic replusion. Like charges in the nucleus repel so can't be combined. Not a viable method at the moment as the energy required > energy produced.

Question - Disposing of waste vs Restoring waste in the nuclear reactor:
Disposing of waste involves burying at sea in concrete or sending in to space. If the concrete is eroded over time cracks may be produced and radiation can contaminate water. If there is an accident whilst launching nuclear material to space, the nuclear fallout would spread over a very large area and many people would die. Restoring of waste involves powering the nuclear reactor - chances of an accident in the reactor which would be catastrophic, chances of accident whilst transporting the fuel rods to be reused... etc.

Question - Thermistor heating up:
As electricity passes through the component, some electrical energy is converted to thermal energy (by colliding with ions in the lattice structure)

Question - Electrical energy production in a nuclear power plant:
Energy released from nuclear reactions heats up water into steam which drives a turbine. Turbine drives a motor which then makes the generator turn. Kinetic energy transferred to electrical energy.

Question - Momentum: Woman & child on ice rink - different speeds:
Child has a lower mass, so will have a higher velocity. Woman has a higher mass, so will have a lower velocity. (Momentum = Mass x Velocity) - link to equation. Before momentum = After momentum (conserved) so obviously the child has to move faster to compensate for her smaller mass.

Question - cloth and tube I think?
Cloth is positively charged because it has lost electrons.

Question - Why the papers /\ <- were like that in the diagram:
Both papers had the same charge when rubbed by the other object (forgot what it was) Like charges repel due to electrostatic repulsion so that's why they were away from eachother.

Question - Why a charge built up on a plane would be dangerous whilst refuelling:
As the nozzle touches the plane, the charge acquired on the fuselage of the plane would discharge. This could create a spark which would ignite the fuel vapour; potentially leading to an explosion.

Question - Bonding line and metal rod attaching fuel tanker and plane:
Metal rod combines both the fuel tanker and plane in terms of charge because metal is a conductor. Other metal rod acts as a bonding line to earth any of the charges that the plane may have acquired to prevent a spark.

Question: Work out the current of the kettle. Had a power rating of 1.8kW and a mains voltage of 230.
1800/230 = 7.83.

Question: Why are Gamma rays used in the irridation of food?
To kill microbes.

Question: What is 1 volt equal to?
1 Volt = 1 Joule/Coulomb.

Question: Something to do with a kettle:
Answer - 216000

sorry what was the question for 'power'?
Question: Work, power:
a) Power
b) The work done is equivalent to the energy transferred.

Crap I messed up the ice rink question, I mixed them up but I said because of the different masses, could I get one mark at least?

It's 7.83 x 230 x 120 = 216108

Well because you mentioned the fact that different masses result in a different velocity I assume you should get at least 1 mark.

It's 7.83 x 230 x 120 = 216108

Post the questions. I can't remember them all.

Question - Half life:
Half life period - 5.4 years.
8000bq -> 1000bq = 16.2 years.

Question: Acceleration equation:
Acceleration = Change in velocity/Time taken
1.2 = 7/x
7/1.2 = 5.833333.

Question: Isotopes:
The two isotopes have the same number of electrons and protons but differing number of neutrons. Can't remember exact values.

Question: Father and wheelbarrow question:
450/1.5 = 300N.

Question: Work, power:
a) Power
b) The work done is equivalent to the energy transferred.

Question: Direction of forces - car and truck:
Answer - B in the table (---> <---)

Question - Why don't neutrons have to be slowed in Fusion?:
Answer - Fusion involves no absorption of neutrons... so why would they need to be slowed.

Question - Conditions for fusion & why those conditions are needed:
Very high temperature (millions of degrees C) and pressure or magnetic confinement to overcome electrostatic replusion. Like charges in the nucleus repel so can't be combined. Not a viable method at the moment as the energy required > energy produced.

Question - Disposing of waste vs Restoring waste in the nuclear reactor:
Disposing of waste involves burying at sea in concrete or sending in to space. If the concrete is eroded over time cracks may be produced and radiation can contaminate water. If there is an accident whilst launching nuclear material to space, the nuclear fallout would spread over a very large area and many people would die. Restoring of waste involves powering the nuclear reactor - chances of an accident in the reactor which would be catastrophic, chances of accident whilst transporting the fuel rods to be reused... etc.

Question - Thermistor heating up:
As electricity passes through the component, some electrical energy is converted to thermal energy (by colliding with ions in the lattice structure)

Question - Electrical energy production in a nuclear power plant:
Energy released from nuclear reactions heats up water into steam which drives a turbine. Turbine drives a motor which then makes the generator turn. Kinetic energy transferred to electrical energy.

Question - Momentum: Woman & child on ice rink - different speeds:
Child has a lower mass, so will have a higher velocity. Woman has a higher mass, so will have a lower velocity. (Momentum = Mass x Velocity) - link to equation. Before momentum = After momentum (conserved) so obviously the child has to move faster to compensate for her smaller mass.

Question - cloth and tube I think?
Cloth is positively charged because it has lost electrons.

Question - Why the papers /\ <- were like that in the diagram:
Both papers had the same charge when rubbed by the other object (forgot what it was) Like charges repel due to electrostatic repulsion so that's why they were away from eachother.

Question - Why a charge built up on a plane would be dangerous whilst refuelling:
As the nozzle touches the plane, the charge acquired on the fuselage of the plane would discharge. This could create a spark which would ignite the fuel vapour; potentially leading to an explosion.

Question - Bonding line and metal rod attaching fuel tanker and plane:
Metal rod combines both the fuel tanker and plane in terms of charge because metal is a conductor. Other metal rod acts as a bonding line to earth any of the charges that the plane may have acquired to prevent a spark.

Question: Work out the current of the kettle. Had a power rating of 1.8kW and a mains voltage of 230.
1800/230 = 7.83.

Question: Why are Gamma rays used in the irridation of food?
To kill microbes.

Question: What is 1 volt equal to?
1 Volt = 1 Joule/Coulomb.

Question: Something to do with a kettle:
Answer - 216000

It was a 3 mark question right?

Yeah it was

there was a question about WORKING out a resultant force... irmemeber part of my working had 1608 is something like that