Barbara places an object in front of a mirror. the mirror produces an image that is inverted, real, and smaller than the object which kind(s) of mirror could barbara be using?
a convex, because concave and plane mirrors produce only virtual images.
b concave, because plane and convex mirrors produce only upright virtual images.
c concave or convex, because both types of mirrors produce images that are inverted and real.
d convex or plane, because both types of mirrors produc image that is smaller than the object.

B). concave, because plane and convex mirrors produce only upright virtual images.

Explanation:

As we know that plane mirror always forms virtual image in which size of image is always equal to the size of the object.

Also we know that mirror formula is given as

here as object is placed in front of mirror so

also the focal length of convex mirror is always positive

So here convex mirror will always form virtual image which is of small size.

So in the given case when image formed is real and inverted we can say that it must be due to convex mirror.

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27