A vertical stick of length 6 m casts a shadow 4 m long on the ground and at the same time a tower casts a shadow 28 m long. Find the height of the tower.

Let AB be a tower


CD be a stick , CD = 6m


Shadow of AB is BE = 28cm


Shadow of CD is DF = 4m


At same time light rays from sun will fail on tower and stick at the same angle


So, <DCF = <BAE


And <DFC = <BEA


< CDF = <ABE (Tower and stick are vertically to ground)


Therefore ΔABE ~ ΔCDF (By AAA similarity)


So, AB/CD = BE/DF


AB/6 = 28/4


AB/6 = 7


AB = 7 x 6


AB = 42 m


So, height of tower will be 42 meter.


24