Author Topic: october november 2009 physics doubt  (Read 788 times)

Offline angell

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october november 2009 physics doubt
« on: March 09, 2010, 08:42:37 am »
Hey

so i had a doubt in Q.3

to calculate the kinetic energy they use 1.66

i just dont get why?

3 A stationary nucleus of mass 220u undergoes radioactive decay to produce a nucleus D of
mass 216u and an ?-particle of mass 4u, as illustrated in Fig. 3.1.

The initial kinetic energy of the ?-particle is 1.0 × 10–12 J.

(b) (i) Show that the initial speed of the ?-particle is 1.7 × 107 m s–1.



help, please?
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oh mehndiya kara dey..
oh jhanjara pawan dey...
On the dance floor oh mundiye...Nach Baliye!

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Offline angell

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Re: october november 2009 physics doubt
« Reply #1 on: March 09, 2010, 08:46:46 am »
(b) (i) kinetic energy = ½ mv2
1.0 × 10-12 = ½ × 4 × 1.66 × 10-27 × v2
v = 1.7 × 107 m s-1


now WHY are they multiplying it 1.66?
oh churiyaan charha dey..
oh mehndiya kara dey..
oh jhanjara pawan dey...
On the dance floor oh mundiye...Nach Baliye!

--~*O yaara dhol bajaake.. O yaara jashan mana ke!!




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Offline astarmathsandphysics

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Re: october november 2009 physics doubt
« Reply #2 on: March 09, 2010, 08:48:58 am »
mass of proton or neutron

Offline angell

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Re: october november 2009 physics doubt
« Reply #3 on: March 09, 2010, 09:11:12 am »
since when did the mass of a proton become 1.66

and we haven't done nuclear physics yet..maybe thats why.
oh churiyaan charha dey..
oh mehndiya kara dey..
oh jhanjara pawan dey...
On the dance floor oh mundiye...Nach Baliye!

--~*O yaara dhol bajaake.. O yaara jashan mana ke!!




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Offline ~Mimi~

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Re: october november 2009 physics doubt
« Reply #4 on: March 21, 2010, 03:33:08 pm »
The rest mass of a proton is given on the first page of the exam.