The gas- powered mower is
(98dB - 70dB) = 28 dB louder.
28 dB = 10^2.8
= 631 times as much sound power.
Explanation:
For, heating purposes more the quantity of water more will be the heating. Clearly, underground heating would have more water and hence, it will have edge over the water heater system.
Moreover, for things at the same temperature, the thing with more molecules has more total kinetic energy (thermal energy) than the thing with fewer molecules. The groundwater heating system uses heat from the heat stored naturally in groundwater or aquifers. Thus, saving the cost of power required to heat in normal water heater.
Answer:
Total 3 holes are available for conduction of current at 300K.
Explanation:
In order to develop a semiconductor, two type of impurities can be added as given below:
- N-type Impurities: Pentavalent impurities e.g. Phosphorous, Arsenic are added to have an additional electron in the structure. Thus a pentavalent impurity creates 1 additional electron.
- P-type Impurities: Trivalent impurities e.g. Boron, Aluminium are added to have a positive "hole" in the structure. Thus a trivalent impurity creates 1 hole.
Now for estimation of extra electrons in the impured structure is as

Now for estimation of "holes" in the impured structure is as

Now when the free electrons and "holes" are available in the structure ,the "holes" will be filled by the free electrons therefore

So total 3 "holes" are available for conduction of current at 300K.
Answer:
True
Explanation:
Insight therapies are very powerful psychological tools used by therapist to help them unlock their past and provide a better well being and a more sound future.
- It involves verbal communication between the client and the therapist.
- The stages are grouped into sessions where both parties frequently meet.
- Issues in the past that might be the premise of current behaviors are focused on.
- The goal is to be able to annul the effect such issues currently have on the present lifestyle of the client.
Explanation:
voltage = current × resistance
5.
12 V = 4.2 A × resistance
resistance = 12 V / 4.2 A = 2.857142857... Ohm
FYI :
4.2 A would be a lot for a small electronic device like a CD player. that would be 12×4.2 = 50.4 Watt, and the CD player would get really hot.
6.
120 V = current × 12 Ohm
current = 120 V / 12 Ohm = 10 A