Which force is indicated by the red arrow in the diagram above?

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What does the length and direction of each arrow on a free body diagram indicate? 

The length of each arrow indicates the magnitude of that force.


The direction of each arrow indicates the direction of the force.

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What is a resultant force?

The resultant force is the overall force acting on an object, taking into account all the different forces acting on it.

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Using the free body diagram above, what is the resultant force acting on the car? 

0 N


(both arrows are the same length, meaning both the forces acting on the car are equal)

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What does it mean for the forces acting on an object to be in equilibrium?

All the forces acting on an object balance out.

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What is the resultant force acting on the car?

200 N to the right.

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In terms of 'acceleration' and 'direction' (left or right), describe the car's motion in the above diagram.

The car is accelerating to the right.


(because the resultant force is 200 N acting to the right, the car will accelerate to the right)

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The car is travelling at 45 mph.


Assuming the forces shown in the free body diagram remain constant, what will the car's velocity be in 30 seconds time?

45 mph.


(because the two 600 N forces acting on the car are equal, the resultant force acting on the car is 0, therefore the velocity of the car will stay the same)

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