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Having trouble understanding the explanations in the answer key. Can anyone help me?
Tbr optics
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Having trouble understanding the explanations in the answer key. Can anyone help me?
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Answer is D right?
Thought process:
--assume height = reference for vision ie eye level
Someone standing 1m from the mirror who is 2 meters tall and one meter away could look down at a 45 degree angle. On its way back you can imagine the ray reflecting off the mirror and hitting there feet, thus A is false.
B is false because the person could see any part of their body by adjusting their view from horizontal to looking at the midpoint of the mirror (which would then reflect to their feet).
C is false because someone 4 feet away and only .5m tall could see their head by looking at eye level or there feet by looking at the part of the mirror .25m above the ground.
D is correct because the person is too close to the mirror to be able to see all of their body. At eye level if they looked down, you can imagine that the ray would hit the ground (due to its steep angle) instead of their feet.
Thought process:
--assume height = reference for vision ie eye level
Someone standing 1m from the mirror who is 2 meters tall and one meter away could look down at a 45 degree angle. On its way back you can imagine the ray reflecting off the mirror and hitting there feet, thus A is false.
B is false because the person could see any part of their body by adjusting their view from horizontal to looking at the midpoint of the mirror (which would then reflect to their feet).
C is false because someone 4 feet away and only .5m tall could see their head by looking at eye level or there feet by looking at the part of the mirror .25m above the ground.
D is correct because the person is too close to the mirror to be able to see all of their body. At eye level if they looked down, you can imagine that the ray would hit the ground (due to its steep angle) instead of their feet.
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With a plane mirror the distance does not matter for this question - it only effects the image distance.
The height of a plane mirror needs to be a minimum of half the object height to show the full image.
I would like to meet this 4 meter tall person!
The height of a plane mirror needs to be a minimum of half the object height to show the full image.
I would like to meet this 4 meter tall person!
