Answer:
E = 124.7 N / C
Explanation:
Let's analyze the exercise: the microwave creates an electromagnetic wave of frequency F = 2.45 GHz, this wave is introduced into the microwave cavity and is reflected on the metal walls, which is why one or more standing waves are formed.
The electric field of the standing wave is
I = E²
E =√I
where I is the intensity of the radiation.
What is it
I = P / A
where P is the effective emission power, almost all the power of the microwave and A is the area of the cavity, in the most used microwaves
P = 700 W and the area is A = 25 x 18 cm² = 0.045 m²
I = 700 / 0.045
I = 15555.56 W/m²
let's calculate the electric field
E = √15555.56
E = 124.7 N / C
<u>Answer:</u>
Things become hot and cold because of the transfer of energy.
<u>Explanation:</u>
The energy possessed by an object or system is called thermal energy and heat is the flow of this energy. While the law of conversation of energy states that energy is not destroyed or created, it just transfers from one object to another.
When a hot object is placed in normal conditions, it transfers heat to the environment until both are at the same temperature and heat transfers from the environment to the cold objects placed in normal conditions.
Answer:
The average impact force is 12000 newtons.
Explanation:
By Impact Theorem we know that impact done by the sledge hammer on the chisel is equal to the change in the linear momentum of the former. The mathematical model that represents the situation is now described:
(1)
Where:
- Average impact force, in newtons.
- Duration of the impact, in seconds.
- Mass of the sledge hammer, in kilograms.
,
- Initial and final velocity, in meters per second.
If we know that
,
,
and
, then we estimate the average impact force is:


The average impact force is 12000 newtons.
In practice, something that follows a very predictable pattern can be used as a time standard. This include things like radioactive decay, planetary orbit, and the speed of light, among others.