Answer:
W = 641.52 J
Explanation:
The work done here will be the sum of potential energy and the kinetic energy of the boy. Here potential energy accounts for vertical motion part while the kinetic energy accounts for the horizontal motion part:

where,
W = Work Done = ?
m = mass = 6 kg
v = speed = 4.2 m/s
g = acceleration dueto gravity = 9.81 m/s²
h = height = 10 m
Therefore,

W = 52.92 J + 588.6 J
<u>W = 641.52 J</u>
A small pebble would sink in water because it is to light and can’t hold itself up in the water. Hope this helped!
Answer:
The frequency of radiation is 
Explanation:
Given:
Wavelength
m
Speed of light

For finding the frequency of radiation,




Therefore, the frequency of radiation is 
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