Answer:
A. The wavelengths of the new sound waves are longer
Explanation:
This is the Doppler effect which can be best illustraded for the case of a siren of an ambulance approaching us having a greater frequency and getting lower in frequency and deeper as the ambulance passes us.
Since the wavelength is inversely proportional to the frequency it follows the wavelengths are longer when the frequency decreases lowering its pitch and getting deeper.
The answer is B friction force
The strong nuclear force overcomes the electric force of repulsion thatacts among the protons in thenucleus. B. The weak nuclear force is involved in certain types of radioactive processes. A.The strong nuclear force is a powerful force of attraction that acts only on theneutrons and protons in the nucleus.
An amplifier.
Electrical energy provided to an amplifier is converted into sound energy as it is "fed" or provided to the speaker portion of an amplifier.