Answer: 653.33 nm ; 1875, 24 nm
Explanation: For the first case we have to use the Balmer series for the hydrogen when the atom falls from the n = 3 to the n = 2. So for the second transtions for the hydrogen we use the Paschen serie. To do the calculation we need to know the Ryberg constant that is equal to 1.097 * 10^7 m^-1. In the attach is shown the expression for spectral series used for calculation.
Answer:
“Measurement” is the act of determining a target's size, length, weight, capacity, or other aspect. There are a number of terms similar to “measure” but which vary according to the purpose (such as “weight,” “calculate,” and “quantify.”) In general, measurement can be understood as one action within the term “instrumentation.”
Explanation:
• To show measured results using values and symbols. • To use measurement tools.
Measuring a target can be done through either direct measurement or indirect measurement. An Indirect measurement is done, for example, by using a dial gauge to measure the height difference between a measurement target and a gauge block and using that height to indirectly determine the target's height. Because this type of measurement is based on a reference, indirect measurement is also referred to as “comparative measurement.
An ”Direct measurement is measurement done by bringing the target into contact with the measurement system to read the length, height, or other aspect directly. Although direct measurement allows measurement results to be known as they are, errors may occur depending on the skill of the person doing the measurement.
Sound travels better in water
Answer:
Current in the speaker will be 1.442 A
Explanation:
We have given an audio amplifier of rms emf of 15 volt
So emf of the audio amplifier 
Resistance of the amplifier 
We have to find the current
From ohm's ;aw we know that V = IR , here I is current and R is resistance
So 
I = 1.442 A
So current in the speaker will be 1.442 A
