Wanna pick the fastest checkout line? Jay Ingram says science can ring you through

Why do our eyes close when we sneeze? Why can't you tickle yourself? Why can some people snap their fingerswhile others can't?

Jay Ingram thought you might be interested in finding answers to these questions.

And as an author, broadcaster, science journalist and co-founder of Beakerhead, it's not his first rodeo.

"Quite often there isn't a definitive answer to these questions, but it allows you to explore what research people have done," Ingram told The Homestretch.

"And hopefully it inspires people to think more about it."

Keep my ears open

There's a fresh batch of questions in his latest book, The Science of Why 4.

"Don't do the same questions you have done in previous books," he said of the gathering process. "I just try and keep my ears open because people wonder about things randomly in conversations."

Sometimes, questions just drop into his lap.

"I was in China and a woman saw me snap my fingers. She can't do it. She makes the motion but there is no sound. I thought, there's a question. How do you make the sound when you snap your fingers and why can't some people do it?"

Want to know how to pick the fastest checkout line at your local grocery store?

Here's how Ingram approached that eternal question.

"It takes much longer to process each order than it does to check each item. It's like three seconds to check an item but 40 seconds to process the transaction. So you might think the express line is the best, but maybe not," he said.

Get behind giant cart

"Somebody with only 10 items is encouraging but you have to remember the transaction is still going to take the same time. So if you have three or four people in the express line but one giant cart in the other line, go behind the giant cart because each of those items will take three seconds, then one transaction and you are done."

Self checkouts, Ingram says, skew the existing research.

"Unfortunately, though, the really good research was done before self checkouts came on the scene. But my experience with self checkout is I am much slower than a cashier. 'Please take the item out of the bag.' Why? I don't want to do that?" he said, with a laugh.