To solve this problem we will apply the concept of magnification, which is given as the relationship between the focal length of the eyepieces and the focal length of the objective. This relationship can be expressed mathematically as,

Here,
= Magnification
= Focal length eyepieces
= Focal length of the Objective
Rearranging to find the focal length of the objective

Replacing with our values


Therefore the focal length of th eobjective lenses is 27.75cm
DescriptionThe mere-exposure effect is a psychological phenomenon by which people tend to develop a preference for things merely because they are familiar with them.
Answer:
4.62 s
Explanation:
We are given that
Initial angular speed,



Substitute the values






Hence, the wheel takes 4.62 s to come to rest.
Answer:
Maximum distance of image from mirror is equal to focal length of the mirror
Explanation:
As we know by the equation of mirror we have

here we know for convex mirror
object position is always negative as it will be placed behind the mirror always
while the focal length of the convex mirror is always taken positive
So here we have


so here maximum value of image distance is equal to focal length of the mirror
Answer:
D: Conducts electrcity poorly
Explanation:
Most conductors are metals, and non- metals are insulators, therefore they dont conduct electricity