Answer:
55.8 m/s
Explanation:
= Actual frequency of sound emitted by car
= frequency observed when the car moves = 
= Speed of sound = 343 m/s
= Speed of car
Frequency observed is given as
Answer: D
1200
Explanation:
Song 1 is spotted with a cube sign.
At 3 minute, trace the spot to the vertical axis. And you will notice that it a little bit above 10.
Since it is above 10, let assume it is equal to 12.
The number of song downloaded are in hundreds. Therefore, multiply the 12 by 100
12 × 100 = 1200 downloads
Approximately, song 1 has 1200 downloads at minute 3
Answer:
Explanation:
= Charge at 3000 m = 40 C
= Charge at 1000 m = -40 C
= 3000 m
= 1000 m
k = Coulomb constant = 
Electric field due to the charge at 3000 m
Electric field due to the charge at 1000 m
Electric field at the aircraft is 
.
Answer:
Option B
Explanation:
The phase difference is found by subtracting the 2.3m for the receiver from the other speaker which is 2.9m hence
Phase difference= 2.9-2.3= 0.6
The magnitude of the displacement of the car from the starting point to halfway around the track is 256 m.
Answer:
Explanation:
Since the race track is a circular track, the distance for one lap will be equal to the circumference of the circular track. And the circumference will be equal to the circumference of the circle.
Since the radius of the track is given as 200 m, then the circumference of the circular track will be
Circumference = 2πr = 2 × 3.14 × 200
So the circumference of the circular track = 1256 m.
So the starting point or position of the track is considered as zero and if the car has traveled half way means, the car has covered half of the circumference of the track.
As the circumference = 1256 m, then half of the circumference of the circle = 1256/2 = 256 m.
So the displacement is the measure of difference between the final position and initial position. As here the initial position is zero and the final position is the halfway around the track which is equal to 256 m.
Then Displacement = Final-Initial = 256-0= 256 m.
So the magnitude of the displacement of the car from the starting point to halfway around the track is 256 m.
