# Grade 11 Question: Newton's Third Law -- Calculating acceleration of an airboat

• Ibo7526
In summary, the conversation discusses using a fan on an airboat to change the boat's direction and speed. The equations for net force and acceleration are shown, with the final answer being an acceleration of 0.5 m/s [forward]. A helpful resource for understanding airboat steering is also provided.

#### Ibo7526

Homework Statement
c) How can the fan on the airboat be used to change the direction the boat is travelling in?
How can it be used to increase or decrease the speed of the boat?
d) If the boat is going upstream against a current that has a force of 250 N against the
motion of the boat, find the acceleration of the boat if there is a forward force of 360 N from
the fan. (Remember that the mass of the boat is 220 kg.)
Relevant Equations
Fnet=F1+ F2
Fnet=ma
a=Fnet/m
for c) i need help
d)
Given: Let [forward] be positive.
F 1 = — 250 N
F 2 = 360 N
Unknown: a = ?
Equation: F net= F1+ F2
F net= m a
Solve: F net= (— 250 N) + 360 N = 110 N
F net= m a
a = F net/ m
= 110 N / 220 kg= 0.5 m/s [forward]
Statement: The acceleration of the boat is 0.5 m/s [forward].

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Ibo7526 said:
Homework Statement:: c) How can the fan on the airboat be used to change the direction the boat is traveling in?
How can it be used to increase or decrease the speed of the boat?

for c) i need help

Google Images is often a good resource for questions like this. I did a Google Images search on airboat steerting, and quickly got to this helpful website:

https://www.flatbottomboatworld.com/how-do-airboats-work/

PeroK