If the girl is also near the source of the sound, two alike sets of sounds will be heard.
Answer:
Rapid human population growth has a number of consequences. Population grows fastest in the world's poorest countries. High fertility rates have historically had a strong relation with poverty, and high childhood mortality rates
Explanation:
i got it from goo.gle but i hope that helps:)
have a good day bro
Ozone is a molecule that consists of three oxygen atoms. When high-energy ultraviolet rays strike ordinary oxygen molecules (O2), they split the molecule into two single oxygen atoms, known as atomic oxygen. A freed oxygen atom then combines with another oxygen molecule to form a molecule of ozone. Hydrocarbons and nitrogen oxides come from great variety of industrial and combustion processes. Motor vehicle exhaust and industrial emissions, gasoline vapors, and chemical solvents are some of the major sources of NOx and VOC that acts as a precursor of ozone. In urban areas, the number of automobiles are more and therefore, more production of such harmful gases. These gases in presence of sunlight leads to the formation of bad ozone.
Answer:
Explanation:
mass, m = 1400 kg
height, h = 16 m
initial velocity, u = 21 m/s
final velocity, v = 13 m/s
Work done by engine, We = 80 kJ
Let the work done by the friction force is Wf.
Use the work energy theorem
net work done = change in kinetic energy
work done by engine + work done by friction force + work done by the gravitational force = Change in kinetic energy
80000 + Wf - m x g x h = 0.5 m ( v² - u²)
80000 + Wf - 1400 x 9.8 x 16 = 0.5 x 1400 x ( 169 - 441 )
- 139520 + Wf = - 190400
Wf = 50880 J
