Solution 8.10b
From Mechanics
(Difference between revisions)
(New page: We use the equation <math>\mathbf{v}=\mathbf{u}+\mathbf{a}t \ </math> where, <math>\mathbf{a}=(0\textrm{.}01\mathbf{i}+0\textrm{.}02\mathbf{j}+0\textrm{.}1\mathbf{k})\text{ m}{{\text{s}}...) |
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<math>t=40 \ \text{s} </math>. | <math>t=40 \ \text{s} </math>. | ||
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+ | giving, | ||
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+ | <math>\mathbf{v}=8\ \mathbf{i}+8 \ \mathbf{ j}+((0\textrm{.}01\mathbf{i}+0\textrm{.}02\mathbf{j}+0\textrm{.}1\mathbf{k}))\times 40 =8\textrm{.}4\mathbf{i}+8\textrm{.}8\mathbf{j}+12\mathbf{k}</math> | ||
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+ | This is the ''velocity'' of the aeroplane. The ''speed'' is the magnitude of the velocity. |
Revision as of 10:16, 20 April 2010
We use the equation \displaystyle \mathbf{v}=\mathbf{u}+\mathbf{a}t \ where,
\displaystyle \mathbf{a}=(0\textrm{.}01\mathbf{i}+0\textrm{.}02\mathbf{j}+0\textrm{.}1\mathbf{k})\text{ m}{{\text{s}}^{\text{-2}}}
and from part a)
\displaystyle \mathbf{u}=8\ \mathbf{i}+8 \ \mathbf{ j}\text{ m}{{\text{s}}^{\text{-1}}} \ and
\displaystyle t=40 \ \text{s} .
giving,
\displaystyle \mathbf{v}=8\ \mathbf{i}+8 \ \mathbf{ j}+((0\textrm{.}01\mathbf{i}+0\textrm{.}02\mathbf{j}+0\textrm{.}1\mathbf{k}))\times 40 =8\textrm{.}4\mathbf{i}+8\textrm{.}8\mathbf{j}+12\mathbf{k}
This is the velocity of the aeroplane. The speed is the magnitude of the velocity.