An object is placed 20.0 cm to the left of a convex lens with a focal length of +8.0 cm. Where is the image of the object?

A)28 cm to the right of the lens

B)13 cm to the left of the lens

C)13 cm to the right of the lens
I think its A but I'm not sure

nope: C

1/20 = 1/8 + 1/x
x = -13.3

Well, I can see why you're not sure! So here's a little joke to lighten the mood: Why did the physics book go to the therapist? Because it had too many unresolved issues!

Okay, now let's get back to the question. To find the location of the image formed by a convex lens, we can use the lens formula:

1/f = 1/v - 1/u

Where f is the focal length of the lens, v is the distance of the image from the lens, and u is the distance of the object from the lens. Plugging in the values for this problem:

1/8 = 1/v - 1/20

Solving this equation, we find that the image is formed at a distance of 13 cm to the left of the lens. So, in your case, the answer is B) 13 cm to the left of the lens.

Hope that clarifies things for you!

To find the position of the image formed by a convex lens, we can use the lens equation:

1/f = 1/di - 1/do

Where:
f = focal length of the lens
di = image distance (distance of the image from the lens)
do = object distance (distance of the object from the lens)

Given:
f = +8.0 cm (positive focal length for a convex lens)
do = -20.0 cm (negative because the object is placed to the left of the lens)

By substituting the given values into the lens equation:

1/8.0 = 1/di - 1/-20.0

Simplifying the equation:

1/8.0 = 1/di + 1/20.0

To solve for di, we need to find the least common denominator:

20.0 * 8.0 = 160

Multiplying through the equation by 160:

160/8.0 = 160/di + 160/20.0

Simplifying further:

20.0 = 160/di + 8.0

20.0 - 8.0 = 160/di

12.0 = 160/di

Cross multiplying:

12.0di = 160

Dividing both sides by 12.0:

di = 160/12.0

di = 13.3 cm (approximately)

Therefore, the image of the object is approximately 13 cm to the right of the lens.

The correct answer is: C) 13 cm to the right of the lens.

To determine the location of the image formed by a convex lens, we can use the lens formula:

1/f = 1/v - 1/u

Where:
- f is the focal length of the lens
- v is the distance of the image from the lens (positive for real images, negative for virtual images)
- u is the distance of the object from the lens (positive for objects on the side of the lens from which light is coming)

In this case, the object is placed 20.0 cm to the left of the lens (u = -20.0 cm) and the focal length of the lens is +8.0 cm (since it is a convex lens).

By substituting these values into the formula, we get:

1/8 = 1/v - 1/-20

To simplify the equation, we can multiply through by 8v(-20) to eliminate the fractions:

-20v + 8v = 8(-20)

-12v = -160

Dividing both sides by -12:

v = 160/12

v ≈ 13.3 cm

Therefore, the image of the object is approximately 13.3 cm to the right of the lens.

So, the correct answer is C) 13 cm to the right of the lens.