Quantum Mechanics Answers

Obtain the expectation value of the potential energy 2 2
2
1
V (x) = mw x of the onedimensional
harmonic oscillator in the first excited state
/ 2
1/ 2
1
2 2
2
( ) 2 a x ax e
a
x −




 

p
y

what is the velocity of a carbon dioxide molecule at 25 degrees centigrade in a one cubic foot box

The mass of a nucleus is 0.042 amu less than the sum of the masses of 3 protons and 4 neutrons. What is the binding energy per nucleon in 7 3Li ?

Plaese explain in details the standard model ..... quarks , leptons as well as all the elementary particles.

Which of the following is NOT correct?

k⃗ ⋅k⃗ =1
i⃗ ×j⃗ =k⃗
i⃗ ×k⃗ =−j⃗
j⃗ ⋅j⃗ =0

Which of the following is the correct unit of k in the equation of a damped harmonic oscillator given as
−bv−kx=ma
, where b is the damping factor and all the symbols have their usual meaning?


kgms−2

kgs−1

kgms−1

kgs−2

If s is distance and t is time, what must be the dimensions of a and b in the equation
s=asin(bt)
?


[a]=[L]−1
,
[b]=[L]−1

[a]=[T]−1
,
[b]=[L]

[a]=[L]
,
[b]=[T]−1

[a]=[L]2
,
[b]=[T]−2

What are the dimensions of pressure gradient?


MLT−2

ML−2T−2

ML3T−2

M−2L2T−3

Which of the following equations is not dimensionally consistent? the symbols have their usual meaning.


s=ut−gt2

Ft=mv−m0

−kx+F0sinωt=ma

ω2=ω20+αθ

Which of the following quantities have the same dimensions?

moment and power

work and power

torque and work

work and upthrust