Physics
(a) Water falls from a height of 150 m. If the specific heat capacity of water is 4.2 kJ kg-1 °C-1 and g = 10 ms-2, then find the rise in temperature of water.
(b) What is determined by the temperature of a body?
Calorimetry
11 Likes
Answer
(a) Given,
Height = 150 m
Specific heat capacity of water = 4.2 kJ kg-1 °C-1 = 4200 J kg-1 °C-1
g = 10 ms-2
Let, whole of the energy possessed by water at the height is changed to heat energy on striking the bottom then initial energy possessed by water = heat energy gained by water.
mgh = mcΔt
Δt = = = 0.357 °C ≈ 0.36°C
Hence, rise in temperature = 0.36°C
(b) Temperature is a parameter which tells the thermal state of a body (i.e., the degree of hotness or coolness of the body). It determines the direction of flow of heat when two bodies at different temperatures are placed in contact.
Answered By
6 Likes
Related Questions
Write reactions of a nucleus 11X23 when it loses
(a) one proton
(b) one β particle
(c) one α particle
What is meant by electrical resistance of a conductor? State how resistance of a conductor is affected when
(a) a low current passes through it for a short duration and
(b) a heavy current passes through it for about 30 s.
The diagram below shows a magnetic needle kept just below the conductor AB which is kept in North South direction.
(i) In which direction does the needle deflect when the key is closed ?
(ii) Why is the deflection produced?
(iii) What will be the change in the deflection if the magnetic needle is taken just above the conductor AB ?
(iv) Name one device which works on this principle.
(a) Write an expression for the heat energy liberated by a hot body.
(b) Some heat is provided to a body to raise its temperature by 25°C. What will be the corresponding rise in temperature of the body as shown on the Kelvin scale?
(c) What happens to the average kinetic energy of the molecules as ice melts at 0°C?