Question

A sailcraft is stalled on a windless day. A fan is attached to the craft and blows air into the sail which bounces backward upon impact. The boat can what?

Answer 1

The approximate force on a square meter of sail can be calculated using Bernoulli's principle. The force can be compared to the needed force to propel a sailboat.

Step-by-step explanation:

The approximate force on a square meter of sail can be calculated using Bernoulli's principle. Bernoulli's principle states that as the wind flows over the sail, the pressure on the front surface decreases, creating a pressure difference that results in a net force on the sail. The force can be calculated using the formula:

Force = (density of air) × (front velocity2 - back velocity2)

Substituting the known values:

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We can calculate the approximate force on a square meter of sail. The force can then be compared to the needed force to propel a sailboat effectively.

Answer 2

Impulse = change in momentum w bounce

There are 2 impulses acting. Recoil of the fan going the negative direction and the impulse of the air bouncing off the sail. The greater impulse will bounce so the direction will be to the right moving the craft.