Tag: the essence of change

a piece of lead falls from a height of $100m$ on a fixed non-conducting slab which brings it to rest. If the specific heat of lead is $30.6{\rm{ }}cal/kg{\,^ \circ }C,$, the increase in temperature of the slab immediately after collision is 

A metal ring of mass  2.1 kg and of 10 cm radius is revolving about its axis, Making 100/$\pi $ revoluation/s in the liquid is equal to 

The temperature inside and outside a refrigerator are $273\ K$ and $300\ K$ respectively Assuming that the refrigerator cycle is reversible, for every joule of work done, the heat delivered to the surrounding will be nearly

The height of the Niagara falls is $50$ metres, $(1 cal= 4.2 \mathrm\ { J }).$  Assume its mechanical energy can be completely converted into heat energy.

The units of fore and length are made three times of their earlier values. Earlier the energy of a system was $81\ J$. What will be the energy of the same system in new units?

When $1\ gm$. of water at $100^{\circ}C$ is converted into steam occupies $1671\ c.c.$ The amount of work done in converting water into steam is

$1$ calorie is the heat required to increase the temperature of $1g$ of water by $1 ^ { \circ } \mathrm { C }$ from:

If the amount of heat given to a system is $35\, J$ and the amount of work done on the system is $15\, J$, then the change in internal energy of the system is

A geyser heats water flowing at the rate of 3.0 liters per minute from ${ 27 }^{ \circ  }C$ to ${ 77 }^{ \circ  }C$. If the geyser operates on a gas burner, the rate of consumption of the fuel if its heat of combustion is $4.0\times { 10 }^{ 4 }J/g$ per minute is

A certain quantity of heat energy is given to a diatomic ideal gas which expands at constant pressure. The fraction of the heat energy that is converted into work is