9. Exercises

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===Exercise 9.1===
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<div class="ovning">
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A parachutist is falling vertically at a constant speed. He has mass 80 kg. Find the magnitude of the upward force acting on the parachute.
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</div>{{#NAVCONTENT:Answer|Answer 9.1|Solution|Solution 9.1}}
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===Exercise 9.2===
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<div class="ovning">
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Each of the bodies shown below are moving with a constant velocity. Use this to find P and Q.
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[[Image:E9.2.GIF]]
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</div>{{#NAVCONTENT:Answer a|Answer 9.2a|Answer b|Answer 9.2b|Answer c|Answer 9.2c|Solution a|Solution9.2a|Solution b|Solution 9.2b|Solution c|Solution 9.2c}}
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===Exercise 9.3===
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<div class="ovning">
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A bicycle moves with a constant velocity along a straight horizontal road. If the forward force which the cyclist exerts by pedalling is 28 N, what is the magnitude of the resistive force acting on the bicycle and cyclist ?
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</div>{{#NAVCONTENT:Answer|Answer 9.3|Solution|Solution 9.3}}
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===Exercise 9.4===
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<div class="ovning">
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A block, of mass 4 kg, is being dragged across a rough horizontal surface at a constant velocity by a force of 20 N acting parallel to the surface. Find the coefficient of friction between the object and the surface.
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</div>{{#NAVCONTENT:Answer|Answer 9.4|Solution|Solution 9.4}}
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===Exercise 9.5===
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<div class="ovning">
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A skier of mass 60 kg is travelling at a constant speed down a slope inclined 20<math>{}^\circ </math> to the horizontal, subject to; air resistance and friction where the coefficient of friction between skier and the slope is 0.05. Find the magnitude of the air resistance force acting on the skier.
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</div>{{#NAVCONTENT:Answer|Answer 9.5|Solution|Solution 9.5}}
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===Exercise 9.6===
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<div class="ovning">
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A car of mass 1600 kg is towed up a hill of inclined at 5<math>{}^\circ </math> to the horizontal. The car moves with a constant velocity. The tow rope is at an angle of 7<math>{}^\circ </math> to the hill.
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[[Image:E9.6.GIF]]
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Model the car as a particle.
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a) Find the magnitude of the tension in the rope.
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b) Find the magnitude of the normal reaction between the hill and the
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sledge.
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</div>{{#NAVCONTENT:Answer|Answer 9.6|Solution a|Solution 9.6a|Solution b|Solution 9.6b}}

Current revision

       Theory          Exercises      

Exercise 9.1

A parachutist is falling vertically at a constant speed. He has mass 80 kg. Find the magnitude of the upward force acting on the parachute.

Answer
Answer 9.1
Solution
Solution 9.1


Exercise 9.2

Each of the bodies shown below are moving with a constant velocity. Use this to find P and Q.

Image:E9.2.GIF

Answer a
Answer 9.2a
Answer b
Answer 9.2b
Answer c
Answer 9.2c
Solution a
Solution9.2a
Solution b
Solution 9.2b
Solution c
Solution 9.2c


Exercise 9.3

A bicycle moves with a constant velocity along a straight horizontal road. If the forward force which the cyclist exerts by pedalling is 28 N, what is the magnitude of the resistive force acting on the bicycle and cyclist ?

Answer
Answer 9.3
Solution
Solution 9.3


Exercise 9.4

A block, of mass 4 kg, is being dragged across a rough horizontal surface at a constant velocity by a force of 20 N acting parallel to the surface. Find the coefficient of friction between the object and the surface.

Answer
Answer 9.4
Solution
Solution 9.4


Exercise 9.5

A skier of mass 60 kg is travelling at a constant speed down a slope inclined 20\displaystyle {}^\circ to the horizontal, subject to; air resistance and friction where the coefficient of friction between skier and the slope is 0.05. Find the magnitude of the air resistance force acting on the skier.

Answer
Answer 9.5
Solution
Solution 9.5


Exercise 9.6

A car of mass 1600 kg is towed up a hill of inclined at 5\displaystyle {}^\circ to the horizontal. The car moves with a constant velocity. The tow rope is at an angle of 7\displaystyle {}^\circ to the hill.

Image:E9.6.GIF

Model the car as a particle.

a) Find the magnitude of the tension in the rope.

b) Find the magnitude of the normal reaction between the hill and the sledge.


Answer
Answer 9.6
Solution a
Solution 9.6a
Solution b
Solution 9.6b
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