Contrasting the Doppler effect with shock waves, the one that requires the faster source is?
2 answers:
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Answer:
The time for final 15 cm of the jump equals 0.1423 seconds.
Explanation:
The initial velocity required by the basketball player to be able to jump 76 cm can be found using the third equation of kinematics as
where
'v' is the final velocity of the player
'u' is the initial velocity of the player
'a' is acceleration due to gravity
's' is the height the player jumps
Since the final velocity at the maximum height should be 0 thus applying the values in the above equation we get
Now the veocity of the palyer after he cover'sthe initial 61 cm of his journey can be similarly found as
Thus the time for the final 15 cm of the jump can be found by the first equation of kinematics as
where symbols have the usual meaning
Applying the given values we get
Answer:
B
Volume decreases due to less molecular motion of the gas inside the football.
Explanation:
Assuming that the atmospheric pressure (and therefore, the pressure of the air inside the football) remains constant, this means that we can apply Charle's law, which states that:
"For a fixed amount of gas kept at constant pressure, the volume of the gas is proportional to its absolute temperature"
Mathematically:
where
V is the volume of the gas
T is its absolute temperature
In the winter month, the air becomes colder, which means that the temperature of the air (and of the gas inside the football) decreases. As the average kinetic energy of the molecules of a gas is proportional to its absolute temperature, this also means that there will be less molecular motion in the gas, and therefore (as stated by Charle's law) the volume of the gas also decreases.