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
Answer:
457.81 Hz
Explanation:
From the question, it is stated that it is a question under Doppler effect.
As a result, we use this form
fo = (c + vo) / (c - vs) × fs
fo = observed frequency by observer =?
c = speed of sound = 332 m/s
vo = velocity of observer relative to source = 45 m/s
vs = velocity of source relative to observer = - 46 m/s ( it is taking a negative sign because the velocity of the source is in opposite direction to the observer).
fs = frequency of sound wave by source = 459 Hz
By substituting the the values to the equation, we have
fo = (332 + 45) / (332 - (-46)) × 459
fo = (377/ 332 + 46) × 459
fo = (377/ 378) × 459
fo = 0.9974 × 459
fo = 457.81 Hz
Answer:
1. Molecular cloud
2. Close binary
3. Brown dwarf
4. Protostellar wind
5. Thermal pressure
6. Protostellar disk
7. Jet
8. Degeneracy pressure
Explanation:
1. The Sun formed, probably along with other stars, within a large molecular cloud.
2. A Close binary consists of two stars that orbit each other every few days.
3. A Brown dwarf is a "star" so small in mass that its core never gets hot enough to sustain nuclear fusion reactions.
4. Most of the gas remaining from the process of star formation is swept into interstellar space by a protostellar wind.
5. As a protostar's internal temperature increases, its growing thermal pressure helps slow its contraction due to gravity.
6. Planets may form within the protostellar disk that surrounds a forming star.
7. Mass can be lost through a jet of material ejected along a protostar's axis of rotation.
8. A "star" with mass below 0.08 solar mass has its gravitational contraction halted by degeneracy pressure.
Work = force in the direction of the movement x distance = 27 N x 1.7 m
Work = 45.9 joules
Answer: option c.
