8. Exercises
From Mechanics
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</div>{{#NAVCONTENT:Answer|Answer 8.1|Solution a|Solution 8.1a|Solution b|Solution 8.1b}} | </div>{{#NAVCONTENT:Answer|Answer 8.1|Solution a|Solution 8.1a|Solution b|Solution 8.1b}} | ||
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+ | ===Exercise 8.2=== | ||
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+ | A particle is set into motion on a smooth inclined plane. The initial velocity of the particle is 5<math>\mathbf{i}</math> <math>\text{m}{{\text{s}}^{-1}}</math>, its acceleration is -4<math>\mathbf{j}</math> <math>\text{m}{{\text{s}}^{-2}}</math> and its initial position is (<math>18\mathbf{i}+14\mathbf{j}</math>) m, where <math>\mathbf{i}</math> and <math>\mathbf{j}</math> are perpendicular unit vectors that lie in the plane in which the particle is moving. | ||
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+ | a) Find the velocity of the particle after it has been moving for 4 seconds. | ||
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+ | b) Find the position of the particle after it has been moving for 8 seconds. | ||
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+ | </div>{{#NAVCONTENT:Answer|Answer 8.2|Solution a|Solution 8.2a|Solution b|Solution 8.2b}} |
Revision as of 15:46, 12 September 2009
Theory | Exercises |
Exercise 8.1
The acceleration of a jet-ski is (\displaystyle 0.9\mathbf{i}+0.7\mathbf{j}) \displaystyle \text{m}{{\text{s}}^{-2}}. Its initial velocity is 4\displaystyle \mathbf{i} \displaystyle \text{m}{{\text{s}}^{-1}} and its initial position is (\displaystyle 400\mathbf{i}+350\mathbf{j}) m. The unit vectors are directed east and north respectively.
a) Find the velocity of the jet-ski when t = 10 seconds.
b) Find the position of the jet-ski when t = 10 seconds.
Exercise 8.2
A particle is set into motion on a smooth inclined plane. The initial velocity of the particle is 5\displaystyle \mathbf{i} \displaystyle \text{m}{{\text{s}}^{-1}}, its acceleration is -4\displaystyle \mathbf{j} \displaystyle \text{m}{{\text{s}}^{-2}} and its initial position is (\displaystyle 18\mathbf{i}+14\mathbf{j}) m, where \displaystyle \mathbf{i} and \displaystyle \mathbf{j} are perpendicular unit vectors that lie in the plane in which the particle is moving.
a) Find the velocity of the particle after it has been moving for 4 seconds.
b) Find the position of the particle after it has been moving for 8 seconds.