Catch up TV
Series 4: 7. Bike Bell and Line Markings
Today, Maddie is on her bike! She visits a bike workshop to find out why different bike bells make different ringing sounds. Maddie uses her special slow-motion camera to see inside a ring bell so we can see how something called a beater spins around really quickly, hitting a bump called the butt to make a long ringing sound.\n\nNext, Maddie visits a rugby stadium to see how line markings are painted onto the pitch so that the players know where to play. Maddie attaches one of her special cameras to a line marking machine to see how it uses a sensor and a nozzle to keep the lines really straight!
Source: CBeebies
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