A physicist was pulled over by a police officer. The police officer asked
"Do you know that you just ran a red light?"
"No. It appeared to be a green light to me. Maybe I was driving a bit too fast."
"Alright sir", said the officer with a grin on his face. "I'll have to give you a speeding ticket then since you must have been driving at around, hmmmm, 110,000,000 mph. With an extra penalty of $5 per mph over 60 mph, it's just a fine of 550 million dollars."
"Ehhh... Actually, I think I ran a red light."
P.S. Created based on a question in my college physics textbook :)