Explanation:
Electromagnetic waves are different from sound or water waves in such a way that water and sound waves are called mechanical waves that requires a material medium for their propagation.
Electromagnetic waves do no require a material medium for propagation.
- Electromagnetic waves are carried or transported by radiation and this can be passed through vacuums and different other materials.
- But mechanical waves such as water and sound waves requires a material medium for their propagation.
- They cannot pass through a vacuum.
Answer:
(E) Second law of thermodynamics
Explanation:
The second law of thermodynamics can be understood according to Clausius' words: In an isolated system, no process can occur if a decrease in the total entropy of the system is associated with it. These processes are associated with energy transformations, in which a variable is introduced, called entropy that indicates the notion of disorder. Therefore, in any isolated process, the disorder can only grow.
Answer:
Worldwide Radio Communication
Explanation:
The ionosphere is important because it is through the ionosphere that world wide radio communication is possible.
Answer:
(E) a greatly increased number of small particles in Earth’s orbit would result in a blanket of reflections that would make certain valuable telescope observations impossible
Explanation:
The trade is one strong reflection for many weak reflections (and more dangerous near-Earth space travel).
None of the answer choices except the last one has anything to do with the effect of exploding a satellite. When you are arguing that exploding a satellite is ill conceived, you need to address specifically the effects of exploding the satellite.
According to the Law of Conservation of Energy, energy is neither created nor destroyed. They are just transferred from one system to another. To obey this law, the energy of the substances inside the container must be equal to the substance added to it. The energy is in the form of heat. There can be two types of heat energy: latent heat and sensible heat. Sensible heat is energy added or removed when a substance changes in temperature. Latent heat is the energy added or removed at a constant temperature during a phase change. Since there is no mention of phase change, we assume the heat involved here is sensible heat. The equation for sensible heat is:
H = mCpΔT
where
m is the mass of the substance
Cp is the specific heat of a certain type of material or substance
ΔT is the change in temperature.
So the law of conservation of heat tells that:
Sensible heat of Z + Sensible heat of container = Sensible heat of X
Since we have no idea what these substances are, there is no way of knowing the Cp. We can't proceed with the calculations. So, we can only assume that in the duration of 15 minutes, the whole system achieves equilibrium. Therefore, the equilibrium temperature of the system is equal to 32°C. The answer is C.
