# Homework Help: The Uncertainty Relation for Position and Momentum

1. Jul 1, 2013

### knowLittle

1. The problem statement, all variables and given/known data
The position of a 60-gram golf ball sitting on a tee is
determined within +- 1μm. What is its minimum possi-
ble energy? Moving at the speed corresponding to this
kinetic energy, how far would the ball move in a year?

2. Relevant equations
$K\geq\dfrac {\hbar ^{2}} {2ma^{2}}$ Minimum Possible Kinetic E.

3. The attempt at a solution
I have solved it using the above equation. But, I wonder, if I should consider rest energy as well.

When they ask the second question, I sort of think that they only want this minimum kinetic E.
Any ideas?

Danke.

Last edited: Jul 1, 2013
2. Jul 1, 2013

### Staff: Mentor

Just the kinetic energy is interesting here.

3. Jul 1, 2013

Why?

4. Jul 1, 2013

### Staff: Mentor

You can calculate both if you like, but the rest energy cannot be accessed here (as you do not have an anti-golfball), and you are not dealing with relativistic velocities.