Intensity and Wattage


by tadisc
Tags: intensity, wattage
tadisc
tadisc is offline
#1
Dec1-11, 12:34 AM
P: 3
1. The problem statement, all variables and given/known data
OK, so this is a very basic question but i am uncertain what the relationship is. I know its logarithmic, but i don't know how to draw a conclusion. Here is the question:
If you want an amplifier which will give a sound output which is twice as lod as your present 20 W amplifier, what amplifier power should you buy? What if you wanted a sound output four times as loud?


2. Relevant equations



3. The attempt at a solution
I know that the relationship between Intensity and Wattage is logarithmic, but how do i draw a numeric conclusion?
Phys.Org News Partner Science news on Phys.org
Going nuts? Turkey looks to pistachios to heat new eco-city
Space-tested fluid flow concept advances infectious disease diagnoses
SpaceX launches supplies to space station (Update)
Simon Bridge
Simon Bridge is offline
#2
Dec1-11, 05:40 AM
Homework
Sci Advisor
HW Helper
Thanks ∞
PF Gold
Simon Bridge's Avatar
P: 10,990
Are they looking for loudness or intensity?

The wattage of the amplifier is the maximum power it can supply to the signal.
The intensity a wave is the square of it's amplitude.
I suspect you are thinking of decibels.

If you double the amplitude, you get four times the intensity.


Register to reply

Related Discussions
Intensity measured from a point and surface intensity Introductory Physics Homework 4
COMSOL: Integrate intensity field in R^3 to obtain an intensity surface in R^2 Mechanical Engineering 0
HW: What is energy used? What is wattage? Introductory Physics Homework 2
Wattage and efficiency Electrical Engineering 8
Resistor Wattage Electrical Engineering 12