The object's speed will not change.
In fact, after the astronaut throws the object, no additional forces will act on it (since the object is in free space). According to Newton's second law:
![\sum F=ma](https://tex.z-dn.net/?f=%5Csum%20F%3Dma)
where the first term is the resultant of the forces acting on the body, m is the mass of the object and a its acceleration, we see that if no forces act on the object, then the acceleration is zero. Therefore, the acceleration of the object is zero, and its velocity remains constant.
Answer:0.1759 v
Explanation:
Intensity of wave at receiver end is
I=![\frac{P_{avg}}{A}](https://tex.z-dn.net/?f=%5Cfrac%7BP_%7Bavg%7D%7D%7BA%7D)
I=![\frac{3.80\times 10^3}{4\times \pi \times \left ( 4\times 1609.34\right )^2}](https://tex.z-dn.net/?f=%5Cfrac%7B3.80%5Ctimes%2010%5E3%7D%7B4%5Ctimes%20%5Cpi%20%5Ctimes%20%5Cleft%20%28%204%5Ctimes%201609.34%5Cright%20%29%5E2%7D)
I=![7.296\times 10^{-6} W/m^2](https://tex.z-dn.net/?f=7.296%5Ctimes%2010%5E%7B-6%7D%20W%2Fm%5E2)
Amplitude of electric field at receiver end
![E_{max}=\sqrt{2I\mu _0c}](https://tex.z-dn.net/?f=E_%7Bmax%7D%3D%5Csqrt%7B2I%5Cmu%20_0c%7D)
Amplitude of induced emf
=![E_{max}d](https://tex.z-dn.net/?f=E_%7Bmax%7Dd)
=![\sqrt{2\times 7.29\times 10-6\times 4\pi \times 3\times 10^8}\times 0.75](https://tex.z-dn.net/?f=%5Csqrt%7B2%5Ctimes%207.29%5Ctimes%2010-6%5Ctimes%204%5Cpi%20%5Ctimes%203%5Ctimes%2010%5E8%7D%5Ctimes%200.75)
=![17.591\times 10^{-2}=0.1759 v](https://tex.z-dn.net/?f=17.591%5Ctimes%2010%5E%7B-2%7D%3D0.1759%20v)
Answer:
B. 17.15 watts
Explanation:
Given that
Time = 10 seconds
height = distance = 0.7 meters
weight of sack = mg = F = 245 newtons
Power = work done/ time taken
Where work done = force × distance
Substituting the given parameters into the formula
Work done = 245 newton × 0.7 meters
Work done = 171.5 J
Recall,
Power = work done/time
Power = 171.5 J ÷ 10
Power = 17.15 watts
Hence the power expended is B. 17.15 watts
The answer is going to be leaves.