Depends entirely on the judge. It is typical for a defendant to go to jail for a few days on a second offense but not always. You will also have a fine possible restitution and possibly a theft class.
The facts that you have presented subject you to a class B misdemeanor theft.
In Utah, a defendant commits a class B misdemeanor theft when they obtain or exercise unauthorized control over the property of another with the purpose to deprive them thereof and the value of the property or services stolen is less than $500.
Fine-Class B misdemeanor: A fine not to exceed $1,000 , plus a 90% surcharge.
Restitution- The court may order a defendant convicted of this crime to pay restitution.
Imprisonment-Class B misdemeanor: A term in jail not to exceed 6 months.
These are the potential things that can happen. Of course, what will happen to you, is at the judges discretion. That said, because this is your second offense, some judges are more inclined to sentence you to some jail.
However, your attorney may be able to negotiate a resolution that will take jail off the table. If you cannot afford an attorney, request one. If the prosecutor is not looking for jail, he will probably indicate that this is a case that he is not seeking jail.
Hope this helps.