An ideal gas heat engine operates in a Carnot's cycle between $227^{\circ}C$ and $127^{\circ}C$. It absorbs $6\times 10^{4} J$ at high temperature. The amount of heat converted into work is _____.
Work done by 100 calorie of heat is __________.
A person of weight 60 kg wants to loose 5 kg by going up and down 10m high stairs. Assume he burns twice as much fat while going up than going down. If 1 kg of fat is burnt on expending 7000 kcal. How many times must he go up and down to reduce his 7 kg weight? (Take $ g=10 \mathrm{ms}^{-2} ) $
What is $\Delta E$ for a system that does 5 kcal of work by the surroundings when 3 kcal heat is absorbed by the system.
A bullet of mass 10 gm moving with a speed of 20 m/s hits an ice block of mass 990 gm kept on a frictionless floor and gets stuck in it. The amount of ice that melts, if 50% of the lost kinetic energy goes to ice, will be
A steel ball of mass $5$ ${ g }$ is thrown downward with velocity $10$ ${ ms } ^ { - 1 }$ from height $19.5$ ${ m }$ . It penetrates sand by $50$ ${ cm }$ . The change in mechanical energy will be ( ${ g } = 10$ ${ ms } ^ { - 2 }$ )
A block of ice falls from certain height and completely melts. If only 3/4th of the energy is absorbed by the block the height of fall should be
A block of ice at 0 C whose mass is initially 50.0 kg slides along a horizontal surface starting at a speed of 5.38 m/s and finally coming of ice melted as a result of the friction between the block and the surface will be
An ice block is falling from a height. If $75\%$ of the block melts then $h = (g = 10\ ms^{-2})$.
A block of mass 500Kg has dimension $10 \times 5 \times 2m$. It is placed on a table with the largest surface in contract. The work that must be done to turn it an place it so that the smallest surface is in contact with the table