Answer:
a)equal to
Explanation:
properties of a wave
applies in reflection
others include:refraction,diffraction,interference
Answer:
The frequency increases, and the pitch increases
Explanation:
- Doppler's law of sound is applicable in such case when the observer or the sound source or both are moving relative to each other.
- In such a case due to space-time constraint the waveform of the sound adjust themselves so as to obey the law of conservation of energy.
<u>The apparent frequency of the sound for the observer is given by:</u>
....................................(1)
where:
observed frequency
original source frequency
speed of sound
speed of source relative to the observer (taken negative when approaching towards the observer and vice-versa)
speed of observer relative to the source (taken negative when moving away from the source and vice-versa)
<u>According to the given situation, eq. (1) becomes:</u>
Since, 
Therefore
Pitch is very closely related to the frequency, it means that how fast is the amplitude of sound varying with time.
At New Moon the percent illuminated is 0; at First and Last Quarters it is 50%; and at Full Moon it is 100%<span>. During the crescent phases the percent illuminated is between 0 and </span>50%<span> and during gibbous phases it is between </span>50%<span> and </span>100%<span>.
so it depends on the phase
</span>
Explanation:
MA of a machine is its mechanical advantage.
Mechanical advantage is the ability of a machine to multiply force so as to get a work done.
- This is done by minimizing effort and maximizing the load or output.
- A MA of a simple machine with a value of 3 suggests that such a machine will multiply input force by a factor of 3.
- Therefore, such a machine will amplify the force input into the system.
