Suspended by only thick steel cords connected to two towers, the Golden Gate Bridge spans almost 9,000 feet. That’s nearly two miles long— a bridge, dangling in the air, that’s somehow remained standing for almost 100 years. It’s San Francisco’s most iconic landmark, and at the time it was built, funding and completing it was a daunting feat. Even today, the Golden Gate Bridge is a mystery to most. But do not fear— Girlstart has come to the rescue to dispel the science behind this modern-day mystery!
For the girls at Carver Elementary, bridges were a simple concept. Beam bridges are supported by giant abutments that stick in the ground; arch bridges are similar. They both are held up just like the tables you sit at everyday— they feature a surface and obvious supports underneath it.
When the girls looked at a photo of the famous Golden Gate bridge, it looks like it’s operating under the same basic rules as arch and beam bridges. It features two towers anchored to the land, so they’ve got to be holding the bridge up, right? Well, kind of. The towers support the steel cords, but not the actual floor of the bridge. After a round of contemplation, the Carver girls decided that the towers also help prevent the bridge from swaying in the wind. It is a hanging bridge, after all.
Wheels were turning in the Carver girls’ minds. They kind of understood suspension bridges, but they couldn’t fully until it was their turn. The girls received toilet paper tubes, tape, string, and a piece of paper to be the road. The string needed to be the perfect length to provide the right amount of tension to support the bridge, and the towers had to be just the right height. With plenty of trial and error, the girls each had their own miniature suspension bridges that they raced toy cars along.
The Golden Gate Bridge will always be a wonder. It’s massive, it’s expensive, and it crosses a very windy valley. But for the girls of Girlstart, it’s no longer a complete mystery. I guess you could say Girlstart really “bridged” the gap this week.
activities ,education ,engineering ,experiments ,Fun ,girls ,hands-on ,kids ,math ,science ,STEM ,technology 