Combining Kinematics and Dynamics Printer Friendly Version
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A certain 1500-kg car can accelerate from rest to 20 m/s in 8.0 s.
What is its acceleration?
 How large a force would be needed to produce this acceleration?

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A horizontal force of 20 N is required to slide a box along a level floor at a constant velocity of 0.30 m/s.
How large is the friction force opposing the motion?
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A water skier is being pulled by a boat at a constant velocity of 12.0 m/s. The tension in the cable pulling the skier is 140 N.
 How large is the retarding force exerted on the skier by the water and the air?

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A horizontal force of 5000 N is required to give a 1000-kg car an acceleration of 0.20 m/s2 on a level road.
How large of a frictional force opposes the motion?
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A 1500-kg car is to be towed by a truck.
 If the towed car is to be accelerated uniformly from rest to 3.0 m/s in 9.0 s, how large a force must the tow rope support?

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A 900-kg car traveling at 20 m/s collides with a tree and goes 1.60 m before stopping.
What is the magnitude of the average stopping force exerted by the tree on the car?
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A 20.0-kg mass is suspended vertically from a cord.
How strong is the cord if it is just capable of holding the 20.0-kg mass at rest?
 Using the same cord, what would be the maximum upward acceleration you could impart to a suspended 5.0-kg mass?

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A 50-kg woman stands on a spring scale inside an elevator.
If the scale reads the normal force supplied by the floor of the elevator on the woman, what would it read when the elevator is accelerating downward at 3.0 m/s2?
 What would the spring scale read as the elevator approaches the first floor if it slows to a stop at 3 m/sec2?

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A 60-kg prisoner wishes to escape from a third-story window by going down a rope made of bedsheets tied together. Unfortunately, the rope can only sustain a maximum tension of 500 N.
How fast must the prisoner accelerate down the rope if it is not to break?
 Why should he have not slid down the rope at a constant velocity?