Answer: Yes
Air serves as a propagation medium.
Explanation:
Propagation of sound wave require a medium for transmission. Sound is produced by vibrating objects, The matter or substance through which sound is transmitted is called a medium. It can be solid, liquid or gas. Therefore to propagate sounds (human voice) from one end of a lecture hall to the other we need a propagation medium which is air. Air serves as a propagation medium.
30 grams because of conservation
Answer:closed systems
Explanation:
A closed system is one in which matter does not enter or leave the system but there is exchange of energy between the system and its environment. In a closed system, the principle of energy conservation applies. The principle of energy conservation states that energy can neither be created nor destroyed but is converted from one form to another. An example of a closed system is a reaction vessel whose lid is closed.
Answer:
16. 68.18 Km/h
17. 3 miles.
Explanation:
16. Determination of the speed
Distance travelled = 150 Km
Time = 2.2 hours
Speed =?
Speed is simply defined as the distance travelled with time. Mathematically, it is expressed as:
Speed = Distance / time
With the above formula, we can obtain the speed as follow:
Distance travelled = 150 Km
Time = 2.2 hours
Speed =?
Speed = Distance /time
Speed = 150 / 2.2
Speed = 68.18 Km/h
17. Determination of the distance.
Speed = 3 mph
Time = 1 hour
Distance =?
Speed = Distance /time
3 = distance / 1
Distance = 3 miles