Answer:
Anything below 7.0 is acidic, so the range would be 0 to 7.
Neutral is simply 7, in the middle of the scale.
Lastly, anything above 7.0 is basic or alkaline, so that would be 7 to 14.
Good luck, I hope this helps
<h2>Answer: True
</h2>
The <u>Doppler effect</u> refers to the change in a wave perceived frequency when the emitter of the waves, and the receiver (or observer in the case of light) move relative to each other.
In other words, it is the variation of the frequency of a wave due to the relative movement of the source of the wave with respect to its receiver.
It should be noted that this effect bears its name in honor of the Austrian physicist <u>Christian Andreas Doppler</u>, who in 1842 proposed the existence of this effect for the case of light in the stars. Another important aspect is that the effect occurs in all waves (including light and sound). However, it is more noticeable to humans with sound waves.
a) 0.94 m
The work done by the snow to decelerate the paratrooper is equal to the change in kinetic energy of the man:
where:
is the force applied by the snow
d is the displacement of the man in the snow, so it is the depth of the snow that stopped him
m = 68 kg is the man's mass
v = 0 is the final speed of the man
u = 55 m/s is the initial speed of the man (when it touches the ground)
and where the negative sign in the work is due to the fact that the force exerted by the snow on the man (upward) is opposite to the displacement of the man (downward)
Solving the equation for d, we find:
b) -3740 kg m/s
The magnitude of the impulse exerted by the snow on the man is equal to the variation of momentum of the man:
where
m = 68 kg is the mass of the man
is the change in velocity of the man
Substituting,
4. a poor insulator
If rest other things are kept constant or unchanged then a good conductor can be termed as a poor insulator.
No, gravity acts equally on all objects. The crumpled paper falls faster because it resists the drag force due to the atmosphere because of its compact size. A flat piece of paper has an extended body and "catches" the air and falls more slowly. In a vacuum they would fall at the same rate either way.
