Hooked on Science: How the wind from a hurricane damages roofs

Materials

• Cardboard
• Masking tape
• Leaf blower

Instructions

• STEP 1: Using the cardboard and masking tape, create a model of a house that can withstand hurricane-force wind. Why is it important to prepare for and respond to severe weather?
• STEP 2: Place the opening of the leaf blower close to the roof of the house, turn on the leaf blower and observe. What happens to the roof of the house? Using this evidence, redesign the roof to withstand hurricane-force wind.

Explanation

As the fast-moving air from the leaf blower blows over the roof, an area of low pressure forms above the roof. The higher pressure inside the house forces the roof up and into the fast-moving air, tearing the roof off the house. This is known as Bernoulli's principle, which says an increase in the velocity of a stream of fluid results in a decrease in pressure.