Answer:
B
Explanation:
machanical waves like sea waves need a medium.
but electromagnetic waves never need a medium
but can also travel through medium
Answer:
The wavelength of the light emitted by a hydrogen atom for the given transition is 2166 nm.
Explanation:
The energy of nth energy levels of the H atom is given as:
Energy of the seventh energy level =
Energy of the seventh energy level =
Energy of the light emitted will be equal to the energy difference of the both levels.
Wavelength corresponding to energy E can be calculated by using Planck's equation:
The wavelength of the light emitted by a hydrogen atom for the given transition is 2166 nm.
Answer:
the wrong statement is
d) the order of conductivity for different states is gas > liquid > solid
Explanation:
- the correct order is solid > liquid > gas
the thermal conductivity is a property of materials that it values the ability to transmit heat through them. In general, for metals and solid of continuos bodies the conductivity is high.
k = q / ΔT
∴ q: heat flux
∴ ΔT; temperature gradient
When a material undergoes changes of states, the thermal conductivity can change. for example, the conductivity of frozen water (a 0°C) is higer than that of liquid water.....from literature.