Ravi is 1.82m tall. He wants to find the height of a tree in his backyard. From the tree’s base he walked 12.20 m. along the tree’s shadow to a position where the end of his shadow exactly overlaps the end of the tree’s shadow. He is now 6.10m from the end of the shadow. How tall is the tree ?

A man whose eye-level is 2 m above the ground wishes to find the height of a tree. He places a mirror horizontally on the ground 20 m from the tree and finds that if he stands at a point C which is 4m from the mirror B, he can see the reflection of the top of the tree. How height is the tree ?

A storm broke a tree and the treetop rested 20 m from the base of the tree, making an angle of 60^@ with the horizontal. Find the height of the tree.

A man 2 m high walks at a uniform speed of 5km/hr away from a lamp post 6 m high. Find the rate at which the length of his shadow increases?

Two friends A and B (each weighing 40 kg ) are sitting on a frictionless platform some distance d apart. A rolls a ball of mass 4 kg on the platform towards B which B catches. Then B rolls the ball towards A and A catches it. The ball keeps on moving back and forth between A and B . The ball has a fixed speed of 5 m//s on the platform. a. Find the speed of A after he rolls the ball for the first time. b. Find the speed of A after he catches the ball for the first time. c. Find the speed of A and B after the ball has made five round trips and is held by A . d. How many times can A roll the ball? e. Where is the centre of mass of the system A + B + ball at. the end of the nth trip?

An observer of height 1.8 m is 13.2 m away from a palm tree. The angle of elevation of the top of the tree from his eyes is 45^(@) What is the height of the palm tree?

A 1.5 m tall boy is looking at the top of a temple which is 30 meter in height from a point at certain distance. The angle of elevation from his eye to the top of the crown of the temple increases from 30^(@) to 60^(@) as he walks towards the temple. Find the distance he walked towards the temple.

A girl of height 120cm is walking away from the base of a lamp post at a speed of 0.6 m/sec. . If the lamp is 3.6 m above the ground level, then find the length of her shadow after 4 seconds.

A student had a breakfast of 200 food calories. He thinks of burning this energy by drawing water from the well and watering the trees in his school. Depth of the well is about 25 m. The pot can hold 25 L of water and each tree requires one pot of water. How many trees can he water? (Neglect the mass of the pot and the energy spent by walking. ("Take g" = 10 ms^(-2))