Answer:
180°
Explanation:
Friction, if it exists, ALWAYS opposes motion or attempted motion.
Answer:
For the first one c is the answer
For the second one c is also the answer
For the third one is b
Explanation:
I took that
Answer:
B. Light passes through a small opening
Explanation:
Diffraction is one of the properties of wave defined as the bending of wave around corners. It occurs mostly when waves passes through a tiny opening or slit. The type of waveform generated by the wave depends on the type of opening or slit that the medium passes through. The opening can be tiny or large.
Based on the definition, it can be inferred that the situation that causes light waves to diffract is when the light passes through a small opening. For example, the light of a torch passing through a tiny door hole is diffraction.
Can't
----------------------------------
Answer:

T=157.06 N
Explanation:
Given that
Mass of first block = 21.1 kg
Mass of second block = 12.9 kg
First mass is heavier than first that is why mass second first will go downward and mass second will go upward.
Given that pulley and string is mass less that is why both mass will have same acceleration.So lets take their acceleration is 'a'.
So now from force equation

21.1 x 9.81 - 12.9 x 9.81 =(21.1+12.9) a

Lets tension in string is T


T=21.1(9.81-2.36) N
T=157.06 N