The correct answers would be B, and d
Answer:
Speed of the wave is 7.87 m/s.
Explanation:
It is given that, tapping the surface of a pan of water generates 17.5 waves per second.
We know that the number of waves per second is called the frequency of a wave.
So, f = 17.5 Hz
Wavelength of each wave, 
Speed of the wave is given by :
v = 7.87 m/s
So, the speed of the wave is 7.87 m/s. Hence, this is the required solution.
Acceleration = force / mass.
A = 100/50 = 2 m/s^2 .
Answer:
False, Sunspots appear dark (in visible light) due to their low temperature(cooler) than rest of the sun
Explanation:
Sunspots appear dark because they are much cooler( have low temperature than the rest of the surface contained by Sun. As they appear dark, but still they have very temperature that's why so hot. Sunspots have temperatures ranges 3,500 Celsius (3773 kelvin) and the surrounding surface of the sun has a temperature much higher of about 5,500 Celsius(5773 Kelvin). Even if we see a sunspot alone in space, it will glow so brightly.
Learn more about sunspots :
brainly.com/question/27774496
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An example is when u rub your pen on your hair hard that is friction
