Aconcave mirror is to form an image of the filament of a headlight lamp on a screen 8.50 m from the mirror. the filament is 6.00 mm tall, and the image is to be 37.5 cm tall. part a: how far in front of the vertex of the mirror should the filament be placed?
part b: to what radius of curvature should you grind the mirror?

13.6 cm

Explanation:

Given

v(image distance)=-8.5 m

height of object=6 mm

height of image =37.5 cm

and magnification of concave mirror is given by

u=13.6 cm

so object is at a distance of 13.6 cm from mirror.

for focal length

f=-13.4 cm

thus radius of curvature of mirror is R=2f=26.8 cm

helium

oxygen

neon

sodium

96.77 amp

explanation:

rl = 250/100 = 2.5 ohms.

egl = 250 + (100 × 0.1) + 2 = 262 v.

at 700 r.p.m., eg2 = 262 × 700/1000 = 183.4 v.

if ia is the new current, then eg2 - 2 - (ia × 0.1) = 2.5 ia

which means this will give ia = 96.77 amp.