Answer:
Some lenses are used to focus light to a pre-defined point based on the amount of curvature of their surfaces.
In a piano design convex, some surfaces are flat while others has positive lenses (biconvex)
Explanation:
Solution
These lenses are applied to pay attention to light in a point pre-defined based on the amount of curvature of their surfaces.
For that of a plano-convex design, one surface has a positive curve and for biconvex lenses, both surfaces are positively curved while the other remains flat.
when used practically, plano-convex lenses are most commonly used where the object being imaged is far apart from lens.
Explanation:
Given that,
The box of oranges cannot exceed a mass of 10.222 Kg if we are sending to a friend by mail.
The mass of each orange is 198 g
We know that,
1 kg = 1000 g
10.222 kg = 10.222×1000 g
Let there are n number of oranges. So,

It means she can send 52 oranges and it is maximum quantity.
Answer:
correct option is E
power lens is - 1.667 D
Explanation:
Given data
infinity = 60 cm
to find out
power lens
solution
we know here infinity v = -60 cm because object at infinity
and we take u = - infinity
so we know that
1/f = 1/v - 1/u
1/f = 1 / -60 - 1 / -infinity
so
1/f = - 1/60
f = - 60 cm = 0.60 m
and we know power of lens = 1/f
so here
power = 1 / -0.60
power = - 1.667 D
so correct option is E
power lens is - 1.667 D