Answer:
77.96dB
Explanation:
Recall that decibels are a unit of measuring intensity of sound, and depend on the logarithm of the intensity
the intensity, measured in decibels is given by:
I(db)=10log(I/I0)
I is the intensity in MKS units; I0 is the threshold intensity for human hearing (10^-12 W/m^2)
Thus, if the two sounds together have a dB of 81, we know:
81=10log(I/I0)
using the data above, we can find the intensity of the two sounds to be
0.000125 W/m^2
therefore, one firecracker has an intensity half of that, or 0.0000625W/m^2
now use this value to find the dB of one firecracker:
I(dB0=10log(0.0000625/10^-12)=77.96dB
Answer:
Magnets can create electricity and electricity can create a magnetic force.
Both electric charges and magnets do not have to touch an object in order to exert a force on it.
Electromagnets use electricity to create a magnetic force.
Explanation:
The process of <u>scientific method</u> involves making hypotheses , driving predictions from them as logical consequences , and then carrying out experiments or empirical observations based on those predictions. A hypotheses is a conjecture , based on knowledge obtained while seeking answers to the questions.
Solar Radiation, The Solar Wind, and Gamma Ray Bursts