dude is -2m/s, ...ettte is +2m/s
pos vel is when dudette, eg, is going in increasing x, in this case.
neg vel is when dudette, eg, is going in decreasing x, in this case. ie she turns round and runs
zero vel is zero speed. dudette standing still
positive vel neg pos top dia
no
yes
yes
yes
yes
yes
all yes looks like ...
1st Law: Objects that are in motion tend to stay in motion. This motion can change with external forces.
<span>If you were to stop pedaling on bike while in motion, you will notice that you will keep moving. This is because a moving body (you) has inertia. If there wasn't any friction between the tires and the ground, between the axles and wheel, any air resistance, or any other force that acts against you, then you could be coasting indefinitely! </span>
<span>2nd Law: Force is equal to the mass times acceleration. </span>
<span>When you pedal, you are applying a force onto the pedal. This force is then translated through tension to apply torque onto the wheel. Turning the wheel will make you accelerate in the lateral direction. </span>
<span>3rd Law: For every action, there is an equal and opposite reaction. </span>
<span>Without this, you could pedal and pedal, but you will be not go anywhere! It is essentially the friction between the tires and the ground that propels you forward. If the ground did not apply to the tire the same amount of force that the tire was applying to the ground, the tire would not "catch" and no friction would be applied. And if there was no third law, the weight of you and your bike would "sink" into the ground because the ground would not be applying a normal force back onto you.
hope this helps and if you have any questions just hmu and ask :)</span>
Answer:
red shift, indicating that the universe is expanding
Explanation:
Doppler effect occurs when a source of a wave (e.g. light, or sound waves) moves relative to an observer; as a result of this relative motion, the wavelength of the wave appears lengthened/shortened to the observer. Two situations can occur:
- The source of the wave is moving towards the observer - in this case, the wavelength of the wave becomes shorter. If the wave is visible light, such as the light emitted by distant galaxies, this means that the wavelength of the light shifts towards the blue-end of the spectrum (blue-shift)
- The source of the wave is moving away from the observer - in this case, the wavelength of the wave becomes longer. If the wave is visible light, such as the light emitted by distant galaxies, this means that the wavelength of the light shifts towards the red-end of the spectrum (red-shift)
In our universe, we observe a red-shift for all the distant galaxies: this means that these galaxies are moving away from us, so this is an indication that the universe is expanding.
Explanation:
It is given that,
Fundamental frequency, f = 220 Hz
(a) We know that at 0 degrees, the speed of sound in air is 331 m/s.
For open pipe, 
l is the length of pipe
Also,
(b) Let f' is the fundamental frequency of the pipe at 30 degrees and v' is its speed.
v' = 348.71 m/s
So, 
f' = 232.4 Hz
Hence, this is the required solution.
Explanation:
As a tornado or other storm system passes over a building, low pressure can tug a roof upward. When those forces surpass the force exerted by the weight of the roof, the structure flies up and is swept away by wind currents..
