Answer:
B temperature is an indirect measurement of the heat energy in a substance
Explanation:
The concept of temperature can be easily understood by looking at what happens when two objects are placed in contact with each other. By common experience, we know that the hotter object transfers heat energy to the colder object, until the two objects are in thermal equilibrium (= they have same temperature).
Thinking about the example above, we can say therefore that the temperature is an indirect measurement of the heat energy possessed by an object (or substance).
For a monoatomic gas, for instance, we define its internal energy as

where n is the number of moles, R is the gas constant, and T is the absolute temperature. From the formula, we see that the temperature is related to the internal energy of the gas, so measuring the temperature means indirectly measuring its internal energy.
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:
A aceleração do carrinho é de, aproximadamente, 1,46 m/s².
Explanation:
F=ma
F: force
m: mass
a: aceleration
66 = 45a
a=66/45= 22/15 ≅ 1,4666 m/s²
Answer:
There are about six to seven million cones in a human eye and are most concentrated towards the macula. Cones are less sensitive to light than the rod cells in the retina (which support vision at low light levels), but allow the perception of color.
Answer:
Independent variable: how far the soccer ball is kicked.
Dependent variable: how well the person does on their math test
Explanation:
The distance the ball is kicked is what the scientist can change. On the other hand, in this experiment, how well the person does on their test supposedly relies on how far the soccer ball is kicked.