A6 cm object is 8 cm from a convex lens that has a focal length of 5 cm. the image is 4 cm from the lens. the height of the image is cm.

So we want to know what is the height of the image if we know the height of the object is H0=6 cm, the distance of the object from the lens is D0=8 cm, the focal length is f=5 cm and the distance of the image is Di=4 cm. The formula for magnification is: M=(Hi/H0)=-(Di/D0) where Hi is the height of the image. We need to find Hi and we can get that form the formula for magnification after we solve for Hi and input the numbers: Hi=-(Di/D0)*H0=-(4/8)*6=-0.5*6=-3 cm. We see that the minus sign tells us that the image is inverted and has a height of 3 cm. 

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