maths help
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maths help
Hi
I need urgent help withindex form problems such as
The mass of a neutron is 1.6725x10-24g electron 9.109x10-28g proton 1.6748x10-24g
An atom of carbon is made up of 6 neutrons 6 protons and 6 electrons
Q1)what is the mass of one at of carbon? IS IT AS SIMPLE AS 75.17 x10-456g
Q2)How many atoms of varbon are there in 1 gram of carbon
I need urgent help withindex form problems such as
The mass of a neutron is 1.6725x10-24g electron 9.109x10-28g proton 1.6748x10-24g
An atom of carbon is made up of 6 neutrons 6 protons and 6 electrons
Q1)what is the mass of one at of carbon? IS IT AS SIMPLE AS 75.17 x10-456g
Q2)How many atoms of varbon are there in 1 gram of carbon
Hi Kate,
No I'm afraid you can't just add the indices together like that.
What you need to do is as follows:
1. Firstly, choose a common index factor, 10-24 is the best in this case.
2. Convert all of the elementary particle weights to the same factor 10-24. In this case this just means dividing the Electron numerator by 10,000. Hence 9.109 x 10-28 = 9.109 div 10,000 (x 10-24)=
0.0009109 x 10-24g
3. Then you can add the various particle weight components together:-
3 (a) 6 neutrons = 10.035 x 10-24
3 (b) 6 protons = 10.0488 x 10-24
3 (c) 6 electrons = 0.0054654 x 10-24
Therefore:-
Q1 The mass of one atom of carbon is 20.0892654 x 10-24grams
Q2 To work out who many atoms of carbon there are in 1 g you divide 1 by the answer to Q1 above:-
1 div ( 20.0892654 x 10-24)
which is the same as
(1 x 10+24) div 20.0892654
or (1 x 10+22) div 0.200892654
4.9778 x 10+24
I have to say that these seems remarkably complex for an 11+ question and I think they would certainly need to have a calculator.
This sounds like the sort of question that they only put as a scholarship question at the end of a Independent Schools maths paper.
What area do you live and where did you get the question from?
No I'm afraid you can't just add the indices together like that.
What you need to do is as follows:
1. Firstly, choose a common index factor, 10-24 is the best in this case.
2. Convert all of the elementary particle weights to the same factor 10-24. In this case this just means dividing the Electron numerator by 10,000. Hence 9.109 x 10-28 = 9.109 div 10,000 (x 10-24)=
0.0009109 x 10-24g
3. Then you can add the various particle weight components together:-
3 (a) 6 neutrons = 10.035 x 10-24
3 (b) 6 protons = 10.0488 x 10-24
3 (c) 6 electrons = 0.0054654 x 10-24
Therefore:-
Q1 The mass of one atom of carbon is 20.0892654 x 10-24grams
Q2 To work out who many atoms of carbon there are in 1 g you divide 1 by the answer to Q1 above:-
1 div ( 20.0892654 x 10-24)
which is the same as
(1 x 10+24) div 20.0892654
or (1 x 10+22) div 0.200892654
4.9778 x 10+24
I have to say that these seems remarkably complex for an 11+ question and I think they would certainly need to have a calculator.
This sounds like the sort of question that they only put as a scholarship question at the end of a Independent Schools maths paper.
What area do you live and where did you get the question from?
maths help
Hi thanks for your response we are moving to Kent and my daughters tutor set the question for practice for 11 plus
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crazy tutor
that sort of question would never appear in the Kent 11+. Buy the NFER practice papers to see the types that are set ......... and maybe get a different tutor!
Or are you aiming for an independent school in Kent which sets this type of question?
Good luck!
p.s. is your tutor a thwarted physicist?
Or are you aiming for an independent school in Kent which sets this type of question?
Good luck!
p.s. is your tutor a thwarted physicist?