Answer:
Halfway between B and A on the return leg.
Explanation:
Your average SPEED for the entire trip will equal your constant speed as the time and distance increase at proportionate rates.
Your average VELOCITY will equal your constant speed while you travel from A to B because time and displacement are increasing at proportionate rates.
When you turn around at B to return, your Displacement is now decreasing while your travel time continues to increase, so your average velocity decreases.
Lets say the distance from A to B is 90 km and your constant speed is 30 km/hr.
your average speed is 30 km/hr because you took 6 hrs to travel 180 km
We want to find your position when your average velocity is 30/3 = 10 km/hr
it took 3 hrs to go 90 km from A to B. Let t be the time lapsed since turn around
your displacement is given by d = 90 - 30(t)
and your total time of travel is t + 3 hrs
v = d/t
10 = (90 - 30t) / (t + 3)
10(t + 3) = (90 - 30t)
10t + 30 = 90 - 30t
40t = 60
t = 1.5 hrs
This will occur when you are halfway between B and A
The subatomic particles that acts like a mini-magnet is electron. Electrons are negatively charged sub atomic particles in an atom. The electron spin is a property of an electron that makes it behave like it's spinning; a spinning electron produces a magnetic field that makes it behave like a tiny magnet in an atom.
The answer would be a.
a chemical change is a change to the chemical makeup of a substance so if the bonds are unchanged it would be a characteristic of a physical change
(6) first choice: the frequency appears higher and wavelength is shorter.
The car approaches a stationary observer and so the sound will appear to have shorter wavelength. This creates an effect of its siren to sound with higher frequency than it would do if both were stationary.
(7) The Doppler formula for frequency in the case of a stationary observer and source approaching it is as follows:

The wavelength is then

The third choice "0.80m; 431Hz" is correct