PART a)
By energy conservation we can say
![PE_i + KE_i = PE_f + KE_f](https://tex.z-dn.net/?f=PE_i%20%2B%20KE_i%20%3D%20PE_f%20%2B%20KE_f)
![mgh_1 + \frac{1}{2}mv_i^2 = mgh_2 + \frac{1}{2}mv_f^2](https://tex.z-dn.net/?f=mgh_1%20%2B%20%5Cfrac%7B1%7D%7B2%7Dmv_i%5E2%20%3D%20mgh_2%20%2B%20%5Cfrac%7B1%7D%7B2%7Dmv_f%5E2)
divide whole equation by mass "m" and plug in all given data
![9.8(1.24) + \frac{1]{2}(1.7)^2 = 9.8(0) + \frac{1}{2}(v)^2](https://tex.z-dn.net/?f=9.8%281.24%29%20%2B%20%5Cfrac%7B1%5D%7B2%7D%281.7%29%5E2%20%20%3D%209.8%280%29%20%2B%20%5Cfrac%7B1%7D%7B2%7D%28v%29%5E2)
![v_f = 5.21 m/s](https://tex.z-dn.net/?f=v_f%20%3D%205.21%20m%2Fs)
so gymnast will reach the floor with speed 5.21 m/s
PART b)
Now the gymnast bend her knees by 0.1 m and comes to rest
so here we will have
![v_f^2 - v_i^2 = 2 a d](https://tex.z-dn.net/?f=v_f%5E2%20-%20v_i%5E2%20%3D%202%20a%20d)
![0 - 5.21^2 = 2(a)(0.1)](https://tex.z-dn.net/?f=0%20-%205.21%5E2%20%3D%202%28a%29%280.1%29)
![a = 135.97 m/s^2](https://tex.z-dn.net/?f=a%20%3D%20135.97%20m%2Fs%5E2)
now the force on the gymnast will be
![F = ma](https://tex.z-dn.net/?f=F%20%3D%20ma)
![F = 50 \times 135.97 = 6798.5 N](https://tex.z-dn.net/?f=F%20%3D%2050%20%5Ctimes%20135.97%20%3D%206798.5%20N)
so during landing the force will be 6798.5 N
The answer would be velocity because its stating the speed and direction of the car.
Answer:
first one is b 2nd one is a 3rd is c and the 4th one is c also
Explanation: have a nice day
1. H2O- The water completely dissolved the salt.
Alcohol- The alcohol dissolved the salt slightly.
Glycerin-The salt has not dissolved at all.
2. Water
3. Like dissolve like basically works on the principle of polarity. It means the substances which possess similar chemical properties may dissolve in each other. For example, ethanol can be dissolved in water because both are polar in nature whereas non-polar molecules can be dissolved in non-polar solvents only.
4. Generally, a solute dissolves faster in a warmer solvent than it does in a cooler solvent because particles have more energy of movement. For example, if you add the same amount of sugar to a cup of hot tea and a cup of iced tea, the sugar will dissolve faster in the hot tea.
Learn more about The choice of solvent here:-brainly.com/question/14918321
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