A concave mirror in an amusement park has a radius ofcurvature of 4.0 m. A child

Question

A concave mirror in an amusement park has a radius ofcurvature of 4.0 m. A child stands in front of the mirror so thatshe appears 2.5 times taller than her actual height. If the imageis upright, how far is she standing from the mirror?

a. 1.2 m
b. 3.5 m
c. 4.0 m
d. 2.8 m
e. 7.0 m A concave mirror in an amusement park has a radius ofcurvature of 4.0 m. A child stands in front of the mirror so thatshe appears 2.5 times taller than her actual height. If the imageis upright, how far is she standing from the mirror? 1.2 m 3.5 m 4.0 m 2.8 m 7.0 m

Explanation / Answer

m=-Di/Do Di = distance to image Do is distance toobject. since the image is up right the image is not real so Di is anegative number. f=r/2 f= focal length= 4/2 =2m 1/f= 1/Do +1/Di however Di=-m*Do 1/f= 1/D0 -1/(m*Do) => Do = f*(1 - 1/m) = 2*(1-1/2.5)=1.2m

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---