What is the name of the perceived change in a sound wave’s frequency due to motion between the observer and the sound source? diffraction
Doppler effect
reflection
resonance

How will the system respond to a temperature increase?

It is really hard for me right know

10 points! will mark brainiest! in a heat engine if 1,000 j of heat enters the system and the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2,000 j 1: write the equation2: list out your known variables 3: plug the numbers into the equations 4: solve 5: write your solution statement that includes initial energy and final energy added you so much!