Question

how are wavelengths affected when they are given off by an object coming towards you? do they get longer or shorter?

Explanation:

This problem relates to the Doppler Effect, a concept in Physics (subfield of Natural Science). When a wave - emitting object moves towards an observer, the waves in front of the object get compressed. Wavelength ($\lambda$) is the distance between successive crests (or troughs) of a wave. As the object moves towards the observer, the distance between these successive crests (wavelength) becomes shorter because the source is catching up with the previously emitted waves, reducing the space between them.

Answer:

The wavelengths get shorter.