- 24 s
- 3 s
- 1.5 s
- 48 s
Statement 2 : Equivalent thermal conductivity of two rods of same physical dimensions and having same thermal conductivity (k), connected to each other in series combination is equal to k.
- Statement 1 is true but statement 2 is false.
- Statement 2 is true but statement 1 is false.
- Both statement 1 and statement 2 are true.
- Both statement 1 and statement 2 are false.
Which of the following cylindrical rods will conduct most heat, when their ends are maintained at the same steady temperature
Length 1 m; radius 1 cm
Length 2 m; radius 1 cm
Length 2 m; radius 2 cm
Length 1 m; radius 2 cm
Why electrical energy is transmitted at high voltage and low current?
[Assume KAI=200 W/m∘C and Kcu=400 W/m∘C]
- 75 W
- 400 W
- 180 W
- 4 W
- temperature difference across AB and CD are equal
- temperature difference across AB is greater than that of across CD
- temperature difference across AB is less than that of across CD
- temperature difference may be equal or different depending on the thermal conductivity of the rod
- heat flow through slabs A and E are same
- heat flow through slab B is minimum
- temperature difference across slab E is smallest
- heat flow through C= heat flow through B + heat flow through D
consider an ice cube of edge 1.0 cm kept in a gravity -free hall. Find the surface area of the water when the ice melts. Neglect the difference in densities of ice and water.
- 209 μF
- 9 μF
- 2 μF
- 265 μF
- 7 μF
- 14 μF
- 21 μF
- 12 μF
[KCu=400 W/m-K, KAl=200 W/m-K, KSteel=50 W/m-K]
Consider two rods of same length and different specific heats (S1 and S2), conductivities K1 and K2 and areas of cross section (A1 and A2) and both having temperature T1 and T2 at their ends. If the rate of heat loss due to conduction is equal, then