As you approach the police car with blaring siren, you hear a change in pitch and frequency. The apparent pitch changes as a result of the Doppler effect. Frequency determines pitch; frequency and wavelength are inversely proportional. You wouldn't "hear" either one. The result is pitch.
The correct answer would be frequency, intensity, and amplitude.
It can be explained with the help of Doppler effects which states that the frequency or wavelength of sound changes (increases or decreases) as source and observer move towards or away from each other.
Due to this effect, the frequency and intensity of siren increase as we move towards the siren.
In addition, amplitude also increases as we move towards the source of the sound and decreases as the observer moves away from the source.
The false statement is 'Electric field lines form closed loops'.
Explanation:
Electric field lines originate from positive end and terminates at negative end,i.e., field lines are inward in direction to the negative charges and outward from the positive charges.
These lines when close together represents high intensity and when far apart shows low intensity of the field.
These lines do not intersect, as the tangent drawn on these lines provides us with the field direction and intersection of these lines means two field directions which is not possible.
These lines unlike magnetic field lines do not form closed loops as they do not turn around but originate at positive end and terminates at negative end which ensures no loop formation.
