Answer:
v = 31.32 [m/s]
Explanation:
To solve this problem we must use the principle of energy conservation, which tells us that potential energy is converted into kinetic energy or vice versa. The potential energy can be calculated by the product of mass by gravity by height.
where:
Epot = potential energy [J]
m = mass = 25 [kg]
g = gravity acceleration = 9.81 [m/s²]
h = elevation = 50 [m]
Now replacing:
![E_{pot}=25*9.81*50\\E_{pot}= 12262.5[J]](https://tex.z-dn.net/?f=E_%7Bpot%7D%3D25%2A9.81%2A50%5C%5CE_%7Bpot%7D%3D%2012262.5%5BJ%5D)
When the rock falls the potential energy is converted into kinetic energy.
where:
Ek = kinetic energy [J]
v = velocity [m/s]
Now clearing v:
![v^{2} =\frac{E_{k}*2}{m}\\v=\sqrt{(2*12262)/25}\\v = 31.32 [m/s]](https://tex.z-dn.net/?f=v%5E%7B2%7D%20%3D%5Cfrac%7BE_%7Bk%7D%2A2%7D%7Bm%7D%5C%5Cv%3D%5Csqrt%7B%282%2A12262%29%2F25%7D%5C%5Cv%20%3D%2031.32%20%5Bm%2Fs%5D)
Answer:
Available options are;
A. validity; high
B. variability; low
C. reliability; low
D. reactivity; high
Answer is C. reliability; low
Explanation:
Normal body temperature is considered to be 37°C (98.6°F); however, a wide variation is seen. Among normal individuals, mean daily temperature can differ by 0.5°C (0.9°F), and daily variations can be as much as 0.25 to 0.5°C. So we can see that the 98 to 106 to 89 degrees shows that the thermometer is not reliable.
Because the coefficient of friction depends on the surface
Wherever the change in the body happened will detect the stimuli and send the signals to the brain and Spinal does
It’s important for a scientist to be open-minded because they need to be able to understand or creative anything that was never thought about. It’s also important for a scientist to be skeptical because some ideas or products that they hear about can have false factors. I hope this helped!
