Posted by Erin on .
An alpha particle (mass 6.6 x 10^-24 grams) emitted by radium travels at 3.4 x 10^7 plus or minus 0.1 x 10^7 mi/h.
(a) What is its de Broglie wavelength (in meters)?
(b) Whats uncertainty in its position?
for part (a) I got 1.53 meters which said it was wrong on Aris and I got 1.56 x 10^-56 meters for part (b) the uncertainty which said it was wrong too.
This is how I solved it please tell me what I did wrong:
part (a) lambda =h/mu
first convert mi/hr to meters/sec
3.4 x 10^7mi/hr = 1.52 x 10^7m/s
(6.626 x 10^-34 kg m^2 s)/(6.6 X 10^-27 kg)x(1.52 x 10^7 m/s)
= 1.53 meters
part (b) delta(x) x m delta u is greater than or equal to h/4 pi.
so, delta (x) is greater than or equal to (h)/ (4 pi) x (m) delta (u)
delta x= (6.626 x 10^-34 kg m^2 s)/ (4 pi) x (6.6 x 10^-27 kg)(4.48 x 10^5 m/s)
= 1.56 x 10^-55 meters
I also converted the mass 6.6 x 10^-24 grams into kilograms, making it 6.6 x 10^-27 kilograms.
Please look this over and correct my error, thank you.
please help me, Aris closes in 35 minutes. it's urgent!
I think you have converted from miles/hour to m/s correctly. But when I put that into the equation, which you appear to have set up correctly, I don't get your answer but something like 6 x 10^-15 or so meters.
Run that calculation through your calculator again and see what you get.