An object is placed at a distance of 20cm from the optical centre of a convex lens of focal length 15cm .find the distance of the image from the lens what will be the height of the image if the object is 4cm tall

       Use the lens form:

                                1/f=1/v-1/u

                                1/30=1/v-(1/-20)

                                 1/30=1/v+1/20

                                 1/30-1/20=1/v

                                  2-3/60=1/v

                                  -1/60=1/v                    ;;;v =  -60 cm

              m = h of image/h of object  =  v/u

                                    H/2 = -60/-20

                                     H = 3*2

                                       H = 6 cm

hi,

what occurs during a solar eclipse?

there are small tides across earth.

the moon is between earth and the sun.

p.s. im not sure if the first answer is correct because during a solar ecliphse there are spring tides and i dont know if they are the same.