Question #43dbd

1 Answer
Apr 22, 2017

sf(lambda_(n)=(h)/(8sqrt(2meV))

Explanation:

I will assume that the charge on the proton is +e and that the alpha particle is 4 times as massive.

The kinetic energy of the proton as it is accelerated through the potential V is given by:

sf(eV=1/2mv^2)

:.sf(v^2=(2eV)/m)

sf(v=sqrt((2eV)/(m))" "color(red)((1)))

The de Broglie wavelength of the proton is given by:

sf(lambda_(p)=h/(mv)" "color(red)((2)))

Substituting the expression for v from sf(color(red)((1))) into sf(color(red)((2))rArr)

sf(lambda_p=h/(msqrt((2eV)/(m)))

The mass of the alpha particle = 4m and the charge = 2e.

:.sf(lambda_(n)=(h)/(4msqrt((4eV)/(m))

sf(lambda_(n)=h/(4m^(1/2).(4eV)^(1/2))

sf(lambda_(n)=h/(4xx2sqrt(meV)))

sf(lambda_(n)=h/(8sqrt(meV)))