<span>Generally speaking, the level of molecular motion is highest in gases, where molecules move around freely in space, bouncing off of each other, and lowest in solids, where molecules are bound together in a rigid structure. As such, the answer would be A; "the molecules in air move more than the molecules in wood".</span>
Answer:
the object will travel 0.66 meters before to stop.
Explanation:
Using the energy conservation theorem:

The work done by the friction force is given by:
![W_f=F_f*d\\W_f=\µ*m*g*d\\W_f=0.35*4*9.81*d\\W_f=13.7d[J]](https://tex.z-dn.net/?f=W_f%3DF_f%2Ad%5C%5CW_f%3D%5C%C2%B5%2Am%2Ag%2Ad%5C%5CW_f%3D0.35%2A4%2A9.81%2Ad%5C%5CW_f%3D13.7d%5BJ%5D)
so:

Answer:
Speed of physicist car is 0.036c or 1.08 x 10⁷ m/s .
Explanation:
Doppler Effect is defined as the change in frequency or wavelength of the wave as the source or/and observer moving away or towards each other.
In this case, the Doppler effect equation in terms of wavelength is :
......(1)
Here
is source wavelength,
is observed wavelength, v is speed of the observer and c is the speed of light.
Given :
Source wavelength,
= 660 nm = 660 x 10⁻⁹ m
Observed wavelength,
= 555 nm = 555 x 10⁻⁹ m
Substitute these values in the equation (1).






v = 1.08 x 10⁷ m/s
Answer:
Yes, if the system has friction, the final result is affected by the loss of energy.
Explanation:
The result that you are showing is the conservation of mechanical energy between two points in the upper one, the energy is only potential and the lower one is only kinetic.
In the case of some type of friction, the change in energy between the same points is equal to the work of the friction forces
= ΔEm
=
-Em₀
As we can see now there is another quantity and for which the final energy is lower and therefore the final speed would be less than what you found in the case without friction.
=
+ Em₀
Remember that the work of the rubbing force is negative, let's write the work of the rubbing force explicitly, to make it clearer
½ m v² = -fr d + mgh
v = √(-fr d 2/m + 2 gh)
v = √ (2gh - 2fr d/m)
Now it is clear that there is a decrease in the final body speed.
Consequently, if the system has friction, the final result is affected by the loss of energy.