a metal rod of length 100cm is heated through 100oC, calculate the change in length of the rod [linear expansivity of the material of the rod is 3 x 10-6K-1]
The image which cannot be formed on a screen is said to be
A
inverted
B
erect
C
real
D
virtual
correct option: d
Any image that can be formed on a screen are called real image. Such images are formed by light rays emanating from the object, when reflected and/or refracted by devices such as lenses and mirrors converge at some specific point.
In contrast there are other images which are formed by the rays of light reaching the observer appearing to converge at some point. This happens when the rays reaching the observer are diverging and when the line of these rays are projected backward. Such images, which cannot be formed on a screen, are called virtual image.