Правка разделов «Statement», «Solution»
en/1.1.1.md
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| + | ### Statement | ||
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| + | $1.1.1.$ Figure$^{*)}$ shows a "blurred photograph" of a jet airplane in flight. The length of the airplane is $30 \text{ m}$, the length of its nose is $10 \text{ m}$. Determine from this "photograph" the speed of the airplane. The shutter exposure time is $0.1 \text{ s}$. The shape of the airplane is shown in the figure with a dashed line. | ||
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| + | #### Solution | ||
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| + | To find the velocity of the airplane it is necessary to determine the vector of its displacement for the time $T$, during which the shutter of the camera is open. Let us select the initial point $1$ in the photograph and determine the distance it will move during the time $T$. The length of the airplane must be subtracted from the total length of the photograph. Taking into account the scale, the modulus of displacement will be | ||
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| + | $$ | ||
| + | l=50-30 = 20 \text{ m} | ||
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| + | For the $0.1 \text{ s}$ aiplane covered a distance of $20\text{ m}$, which corresponds to velocity of | ||
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| + | $$ | ||
| + | \boxed{v = \frac{l}{T} = 200\text{ m/s}} | ||
| + | $$ | ||
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| @@Ixt9s | ### Statement | ||
| $1.1.1.$ Figure$^{*)}$ shows a "blurred photograph" of a jet airplane in flight. The length of the airplane is $30 \text{ m}$, the length of its nose is $10 \text{ m}$. Determine from this "photograph" the speed of the airplane. The shutter exposure time is $0.1 \text{ s}$. The shape of the airplane is shown in the figure with a dashed line. | |||
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| #### Solution | |||
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| To find the velocity of the airplane it is necessary to determine the vector of its displacement for the time $T$, during which the shutter of the camera is open. Let us select the initial point $1$ in the photograph and determine the distance it will move during the time $T$. The length of the airplane must be subtracted from the total length of the photograph. Taking into account the scale, the modulus of displacement will be | |||
| $$ | |||
| l=50-30 = 20 \text{ m} | |||
| $$ | |||
| For the $0.1 \text{ s}$ aiplane covered a distance of $20\text{ m}$, which corresponds to velocity of | |||
| $$ | |||
| \boxed{v = \frac{l}{T} = 200\text{ m/s}} | |||
| $$ | |||