A ladder resting against a vertical wall has its foot on the ground at the distance of 6 cm from wall. A man climbs two third of the ladder. What will be his distance from the wall now ?

A man stands on a rotating platform with his arms outstretched horizontally holding a 5 kg weight in each hand. The angular speed of the platform is 30rpm. The man then brings his arms back to his body with the distance of each weight from the axis changing from 0.90m to 0.20m. The moment of inertia of the man together with the platform may be taken to be constant and equal to 7.6 kgm^2 What is his new angular speed ?

A man stands on a rotating platform with his arms outstretched horizontally holding a 5 kg weight in each hand. The angular speed of the platform is 30rpm. The man then brings his arms back to his body with the distance of each weight from the axis changing from 0.90m to 0.20m. The moment of inertia of the man together with the platform may be taken to be constant and equal to 7.6 kgm^2 Is K.E conserved in the process ? If not, from where does the change come about ?

Deepak's mom was finding difficult to cook in the kitchen as there was power cut, and she was calied Deepak for help. He immediately took a plane mirror from his shelf made it stand against a wall such that sun's rays were focussed into the kitchen due to the reflection of the mirror. There was some lighting and his mother was able to finish her work. What are the characteristic of the image formed by a plane mirror ?

Deepak's mom was finding difficult to cook in the kitchen as there was power cut, and she was calied Deepak for help. He immediately took a plane mirror from his shelf made it stand against a wall such that sun's rays were focussed into the kitchen due to the reflection of the mirror. There was some lighting and his mother was able to finish her work. What values did Deepak display?

A man stands on a rotating platform, with his arms stretched horizontally holding a 5 kg weight in each hand. The angular speed of the platform is 30 revolutions per minute. The man then brings his arms close to his body with the distance of each weight from the axis changing from 90cm to 20cm. The moment of inertia of the man together with the platform may be taken to be constant and equal to 7.6 kg m^(2) . (a) What is his new angular speed? (Neglect friction.) (b) Is kinetic energy conserved in the process? If not, from where does the change come about?

A 70 kg man stands in contact against the inner wall of a hollow cylindrical drum of radius 3 m rotating about its vertical axis with 200 rev/min. The coefficient of friction between the wall and his clothing is 0.15. What is the minimum rotational speed of the cylinder to enable the man to remain stuck to the wall (without falling) when the floor is suddenly removed ?

Sananth was standing outside in the evening, enjoying the light drizzle after the rain. Suddenly tie observed a rainbow in the sky. He called his father and asked him, what it is and how is it formed? His father explained him about its formation and also told him that similar phenomena can be observed with prism also. What is the name of the phenomena ? Which colour deviates more and why ?

Gopal is worrying that his neighbour can peep into his living room from the top floor of his house. He has decided raise the height of the fence that is high enough to block the view from his neighbour’s top floor window. What should be the height of the fence? The measurements are given in the figure.