Why Is the Net Force on Both Cars Zero Despite Different Speeds?

Thread starter Skittles
Start date Sep 13, 2006
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Basic physics Physics

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Both cars experience a net force of zero despite their differing speeds because they are moving at constant velocities. According to Newton's first law, an object in motion will remain in motion at a constant velocity unless acted upon by an external force. Since both cars are not accelerating, the forces acting on them, such as friction and engine thrust, are balanced. The discussion emphasizes understanding that speed alone does not determine net force; rather, it is the presence of acceleration that does. Therefore, the net force on both cars remains zero.

Sep 13, 2006

Skittles

I don't understand this:

A slow car moves at a steady 10 km/hr down a straight highway while another car zooms past at a steady 120 km/hr. Which car is has the greater net force on it?

The answer is neither, because the net force on each car is zero.

Why is it zero?

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Sep 13, 2006

mbrmbrg

Look at the definition of force.

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