Answer:
Light does not need a medium to travel travel through, but since waves must have a medium to vibrate, sound is not created where no air is present.
Explanation:
Sunlight (white light) refracts through droplets of water in the atmosphere and this causes a rainbow in the sky. The correct option among all the options that are given in the question is the third option or option "C". The rainbow is caused by the reflection, refraction and dispersion of sunlight in water droplets that are present in the atmosphere.
Mechanical wave shows dual nature
Potential energy<span> is the </span>energy<span> that is stored in an object due to its position relative to some zero position. It is calculated by the expression PE = mgh where mg is the weight of the book and h is the height. It is calculated as follows:
PE = 50(1) = 50 J
</span>PE = 50(1.5) = 75 J
PE = 50(2) = 100 J
a) PE=mgh=0.2*9.8*1.2=2.352 J
b) KE=PE=2.352 J
c) m/s