9. Exercises
From Mechanics
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</div>{{#NAVCONTENT:Answer|Answer 9.4|Solution|Solution 9.4}} | </div>{{#NAVCONTENT:Answer|Answer 9.4|Solution|Solution 9.4}} | ||
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+ | ===Exercise 9.5=== | ||
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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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+ | 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 | ||
+ | sledge. | ||
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+ | </div>{{#NAVCONTENT:Answer|Answer 9.6|Solution a|Solution 9.6a|Solution b|Solution 9.6b}} |
Revision as of 15:39, 14 September 2009
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.
Exercise 9.2
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 ?
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.
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.
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.
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.