Answer:
31.2 m/s
Explanation:
= Frequency of approach = 480 Hz
= Frequency of going away = 400 Hz
= Speed of sound in air = 343 m/s
= Speed of truck
Frequency of approach is given as
eq-1
Frequency of moving awayy is given as
eq-2
Dividing eq-1 by eq-2
= 31.2 m/s
Temperature and elevation, if it is cold in Idaho and warm on the eastern end of a mountain side in california (or if warm air is going in that direction) then the cold air, being more dense, will go towards california while the cold air in Idaho will become warm. Same goes for the rest of the world
By putting an apple up on high ground. (That is 1 example)
This creates a higher gravitational force, and when it falls down it would have a lot of kinetic energy. But, if put on low ground, it wouldn't have enough potential energy to increase the kinetic energy.
A hologram is a physical structure that diffracts light into an image. The term ‘hologram’ can refer to both the encoded material and the resulting image. A holographic image can be seen by looking into an illuminated holographic print or by shining a laser through a hologram and projecting the image onto a screen. Hope this helps! Oh and here's a good source to use just don't forget to credit the sources you use.
http://file.scirp.org/Html/70316_70316.htm
Answer:
t = 2.5 hours
Explanation:
given,
speed of the bike for t time= 18 mi/h
final speed of the bike after t time = 12 mi/h
total distance, D = 69 miles
total time, T= 4.5 hour
time for which speed of the bike is 18 mi/h = ?
we know distance = speed x time
now,
18 x t + 12 (4.5 - t) = 69
6 t + 54 = 69
6 t = 15
t = 2.5 hours
The bike was at the speed of 18 mi/h for 2.5 hours.
