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
1. Earth's moon has no atmosphere because the moon's gravity is too weak to hold onto gas molecules.
2. On the moon, maria are low flat plains. The word maria comes from the Latin word mare, which means sea.
Answer:
10
Explanation: Earth takes 24 hours to complete one spin, and Mars takes 25 hours. The gas giants rotate really fast. Jupiter takes just 10 hours to complete one rotation. Saturn takes 11 hours, Uranus takes 17 hours, and Neptune takes 16 hours.
"700 watts" means 700 joules of work per second.
"300 watts" means 300 joules of work per second.
If the labels on both machines are true, and both machines
are loaded to their full capacity, then the 700-watt engine
is doing work faster than the 300-watt one.