For an object at distance of 3.00 m, at what distance from the lens is the image formed? the person is farsighted ?

You want this nearsighted person to be able to see very distant objects clearly. That means the spectacle lens must produce an image 30.0 cm from the eye for an object very far away. An image 30.0 cm from the eye will be 28.5 cm to the left of the spectacle lens (see Figure 2). Therefore, we must get di = −28.5 cm when do ≈ ∞. The image distance is negative, because it is on the same side of the spectacle as the object

Explanation:

Since do are known, the power of the spectacle lens can be found using

P

=

1

d

o

+

1

d

i

as written earlier:

P

=

1

d

o

+

1

d

i

=

1

∞

+

1

−

0.285

m

Since

1

∞

=

0

, we obtain:

P

=

0

−

3.51

m

=

−

3.51

D

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.

the ima (higher than 1m) will be greater than the ima with the height of 1m.