To act as the Sun' was accepted but if you put 'sunlight' alone it was not accepted. The examiner wanted you to state that the infra red radiation was needed to warm up the water.
Answer:
The initial velocity is 50 m/s.
(C) is correct option.
Explanation:
Given that,
Time = 10 sec
For first half,
We need to calculate the height
Using equation of motion
![v^2=u^2+2gh](https://tex.z-dn.net/?f=v%5E2%3Du%5E2%2B2gh)
....(I)
For second half,
We need to calculate the time
Using equation of motion
![h =ut+\dfrac{1}{2}gt_{2}^2](https://tex.z-dn.net/?f=h%20%3Dut%2B%5Cdfrac%7B1%7D%7B2%7Dgt_%7B2%7D%5E2)
![h=0+\dfrac{1}{2}gt_{2}^2](https://tex.z-dn.net/?f=h%3D0%2B%5Cdfrac%7B1%7D%7B2%7Dgt_%7B2%7D%5E2)
![t_{2}=\sqrt{\dfrac{2h}{g}}](https://tex.z-dn.net/?f=t_%7B2%7D%3D%5Csqrt%7B%5Cdfrac%7B2h%7D%7Bg%7D%7D)
Put the value of h from equation (I)
![t_{2}=\sqrt{\dfrac{2\times v^2}{g^2}}](https://tex.z-dn.net/?f=t_%7B2%7D%3D%5Csqrt%7B%5Cdfrac%7B2%5Ctimes%20v%5E2%7D%7Bg%5E2%7D%7D)
![t_{2}=\dfrac{v}{g}](https://tex.z-dn.net/?f=t_%7B2%7D%3D%5Cdfrac%7Bv%7D%7Bg%7D)
According to question,
![t_{1}+t_{2}=10](https://tex.z-dn.net/?f=t_%7B1%7D%2Bt_%7B2%7D%3D10)
![t_{1}=t_{2}](https://tex.z-dn.net/?f=t_%7B1%7D%3Dt_%7B2%7D)
Put the value of t₁ and t₂
![\dfrac{v}{g}+\dfrac{v}{g}=10](https://tex.z-dn.net/?f=%5Cdfrac%7Bv%7D%7Bg%7D%2B%5Cdfrac%7Bv%7D%7Bg%7D%3D10)
![\dfrac{2v}{g}=10](https://tex.z-dn.net/?f=%5Cdfrac%7B2v%7D%7Bg%7D%3D10)
![v=\dfrac{10\times g}{2}](https://tex.z-dn.net/?f=v%3D%5Cdfrac%7B10%5Ctimes%20g%7D%7B2%7D)
Here, g = 10
The initial velocity is
![v=\dfrac{10\times10}{2}](https://tex.z-dn.net/?f=v%3D%5Cdfrac%7B10%5Ctimes10%7D%7B2%7D)
![v=50\ m/s](https://tex.z-dn.net/?f=v%3D50%5C%20m%2Fs)
Hence, The initial velocity is 50 m/s.
The medium is the component of communication through which information is transferred. The correct option in the given question is option "c". Medium is actually the means through which communication is done. It can be a an oral message or written message or it can be nonverbal or symbolic. Any kind of message transmission requires a medium and without an medium no message can be transmitted. Whenever people talk on the telephone or write a letter, there has to be a medium for transmitting the message to the person on the other side.
Answer:
about 4 km
Explanation:
15 minutes is a quarter of an hour, so you divide 16km by 4 to get your answer