2) Higher frequency and higher pitch.
Due to the Doppler effect, sounds emitted at a distance have a higher frequency and therefore a higher pitch.
Answer:
F/2
Explanation:
In the first case, the two charges are Q1 and Q2 and the distance between them is r. K is the Coulomb's constant
Hence;
F= KQ1Q2/r^2 ------(1)
Where the charge on Q1 is doubled and the distance separating the charges is also doubled;
F= K2Q1 Q2/(2r)^2
F2= 2KQ1Q2/4r^2 ----(2)
F2= F/2
Comparing (1) and (2)
The magnitude of force acting on each of the two particles is;
F= F/2
Speed of wave is 8000 m/s.
Answer:
Explanation:
Speed is the measure of ratio of distance to time taken to cover that distance. In other words, speed is the measure of how fast the object can be move in a given time interval. So in this case, the wave is considered as object . And wave consists of wavelength in place of distance and frequency as reciprocal of time interval.
So speed of wave is calculated as the product of wavelength and frequency.
As the wavelength is given as 20 m and the frequency is given as 400 Hz, then the speed will be
Speed = wavelength × Frequency = 20 × 400
Speed of wave = 8000 m/s.
So speed of wave is 8000 m/s.
Answer:
New force = 9(initial force)
Explanation:
The force between two charges is given by :

Where
d is the original distance
Let d' is the new distance such that, r' = r/3
New force,

So, the new force becomes 9 times the initial force.