Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
A concave mirror has a focal length of . Find the image distance and the magnification for an object at , , and in front of the mirror. Say what the image is like each time.
New Cartesian signs: distances from the pole, against the incoming light negative. So is negative, a concave mirror has a negative , and a convex mirror a positive . Mirror formula ; magnification . A negative means real and inverted.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. . , so and . Real, inverted, smaller.
Step 2. . The object is at : and . Real, inverted, the same size.
Step 3. . , so and . Real, inverted, larger.
Step 4. . , so and . Virtual, upright, larger.
Answer: , , and ; , , and .
What do we see? As the object comes closer, the real image moves out and grows. Inside the focus, it jumps behind the mirror.
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