Answer
D.Diffraction
Explanation
Diffraction is a property that is experienced by waves when they come across a barrier when they are in motion.
The ways tends to curve behind the barrier. This is called diffraction of waves.
Now, sound is a wave and it also experience diffraction. . So the brother will be able to hear the sound due to diffraction
Your answer is C) The speed of sound is higher in solids than in liquids.
Answer:
Either B or D. The answer itself is 2.
Explanation:
The equation for the kinetic energy would be 1/2*mv^2.
When m is doubled, we can plug in 1 and 2 to compare our answers.
Plugging in 1 for mass would give us the answer 1/2*v^2.
Plugging in 2 for mass would give us v^2. This means that the velocity was multiplied by 2, meaning that the answer is it is multiplied by 2.
I am not sure which answer is correct since there seems to be two answer choices with 2 in it, but the answer is either B or D (I will call it ABCD because I do not want to cause confusion by saying 2 multiple times).
