I would go with the last two because they are the same please give me brainiest if i am right
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Answer:
34.4Joules
Explanation:
Complete question
a man is trying to pull a box a distance of 3 m with a force of 20 N that makes a 35º with the horizontal. Find the workdone
Work done = Fdsin theta
Force F = 20N
distance d = 3m
theta = 35 degrees
Substitute
Workdone = 20(3)sin 35
Workdone = 60sin35
Workdone = 34.4Joules
Hence the workdone by the man is 34.4Joules
Answer:
The bird has 20,000 times higher kinetic energy than the mosquito.
Explanation:
The formula for kinetic energy shows that the amount of energy is proportional to the mass:

The velocity of both objects being the same, the mass is the determiner. The ratio of the kinetic energy of the bird and the mosquito then becomes the ratio of their masses, i.e., 0.02kg/0.00001kg. The bird's energy is 20,000 times higher than that of the mosquito. This proportion becomes more believable if you imagine the event of a distracted errant bird colliding with your head, versus a confused mosquito colliding with your head.
It’s red shift and blue shift because This only occurs when the frequency of the wave is made longer or shorter due to the movement of the source relative to the observer