Answer: (1) The correct answer is A.
(2) The correct answer is D.
Explanation:
(1)
Reflection is the sending back of light from the surface without absorbing it. In the reflection phenomenon, the wave does not continue moving forward.
Diffraction is the bending of the light around the obstacle. In the diffraction phenomenon, the wave travels forward after striking around the obstacle.
Therefore, the correct answer is A.
(2)
Amplitude is the maximum displacement in the medium from the rest position.
The amount of energy is related to the amplitude. Amplitude is related to the amount of energy carried by the wave. Low energy wave is characterized by a low amplitude. High energy wave is characterized by a high amplitude.
Therefore, the correct option is D.
If you are pushing the coin across the table at a constant rate, the friction of the table and the horizontal force of your hand pushing are equal, and the coin itself moves at a constant rate. If you push a coin and let it go, there is no horizontal force keeping the coin going. Friction slows the coin to a stop. In both cases, the gravitational downward pull of Earth is equally but oppositely resisted by the upward push of table on the coin.
india and china produce the most greenhouse gas emissions?
Answer:
μ = 0.33
Equal to 3.2 m/s²
Explanation:
Draw a free body diagram of the block. There are three forces:
Normal force N pushing up.
Weight force mg pulling down.
Friction force Nμ pushing opposite the direction of motion.
Sum of forces in the y direction.
∑F = ma
N − mg = 0
N = mg
Sum of forces in the x direction.
∑F = ma
Nμ = ma
Substitute.
mgμ = ma
μ = a/g
μ = (3.2 m/s²) / (9.8 m/s²)
μ = 0.33
As found earlier, the acceleration is a = gμ. Since g and μ are constant, a is also constant, so it does not change with velocity.
Answer:
D
Explanation:
because it is the only one that has something to do with heat keyword would be boiling
