Answer:
By opening the door, Elijah is using the chemical energy, which he obtained from eating food to do work. Thus, he is converting chemical energy to mechanical energy.
Stretching the spring by opening the screen door convert the potential energy which is stored in the spring to kinetic energy.
Overall there is conversion of chemical energy to potential energy.
By letting the door go, Elijah is using chemical energy. By snapping shut, the door is converting potential energy to kinetic energy. The overall energy change is conversion of chemical energy to kinetic energy.
Explanation:
Answer:
A) Propagation of pressure fluctuations in a medium
B) air is the medium in which the wave is transported,
Explanation:
Part A.
A sound wave is a longitudinal oscillation of the molecules that forms in a material medium, they can be solid, liquid or gases, therefore the wave propagates in the same direction as the oscillation of the particles.
The most correct answer is:
* Propagation of pressure fluctuations in a medium
Part b
air is the medium in which the wave is transported, otherwise it cannot propagate
The "walkie-talkie" is Don Hings' most well-known invention. The earliest versions of this device were designed as portable field radios for the bush pilots of Consolidated Mining and Smeltin , who had to fly their planes between remote sites in the far north of Canada.
Answer:
scientists will use absolute dating to find how old a fossil exactly is.
