Answer:
1) 64.2 mi/h
2) 3.31 seconds
3) 47.5 m
4) 5.26 seconds
Explanation:
t = Time taken = 2.5 s
u = Initial velocity = 0 m/s
v = Final velocity = 21.7 m/s
s = Displacement
a = Acceleration
1) Top speed = 28.7 m/s
1 mile = 1609.344 m
![1\ m=\frac{1}{1609.344}\ miles](https://tex.z-dn.net/?f=1%5C%20m%3D%5Cfrac%7B1%7D%7B1609.344%7D%5C%20miles)
1 hour = 60×60 seconds
![1\ s=\frac{1}{3600}\ hours](https://tex.z-dn.net/?f=1%5C%20s%3D%5Cfrac%7B1%7D%7B3600%7D%5C%20hours)
![28.7\ m/s=\frac{\frac{28.7}{1609.344}}{\frac{1}{3600}}=64.2\ mi/h](https://tex.z-dn.net/?f=28.7%5C%20m%2Fs%3D%5Cfrac%7B%5Cfrac%7B28.7%7D%7B1609.344%7D%7D%7B%5Cfrac%7B1%7D%7B3600%7D%7D%3D64.2%5C%20mi%2Fh)
Top speed of the cheetah is 64.2 mi/h
Equation of motion
![v=u+at\\\Rightarrow a=\frac{v-u}{t}\\\Rightarrow t=\frac{21.7-0}{2.5}\\\Rightarrow a=8.68\ m/s^2](https://tex.z-dn.net/?f=v%3Du%2Bat%5C%5C%5CRightarrow%20a%3D%5Cfrac%7Bv-u%7D%7Bt%7D%5C%5C%5CRightarrow%20t%3D%5Cfrac%7B21.7-0%7D%7B2.5%7D%5C%5C%5CRightarrow%20a%3D8.68%5C%20m%2Fs%5E2)
Acceleration of the cheetah is 8.68 m/s²
2)
![v=u+at\\\Rightarrow t=\frac{v-u}{a}\\\Rightarrow t=\frac{28.7-0}{8.68}\\\Rightarrow t=3.31\ s](https://tex.z-dn.net/?f=v%3Du%2Bat%5C%5C%5CRightarrow%20t%3D%5Cfrac%7Bv-u%7D%7Ba%7D%5C%5C%5CRightarrow%20t%3D%5Cfrac%7B28.7-0%7D%7B8.68%7D%5C%5C%5CRightarrow%20t%3D3.31%5C%20s)
It takes a cheetah 3.31 seconds to reach its top speed.
3)
![v^2-u^2=2as\\\Rightarrow s=\frac{v^2-u^2}{2a}\\\Rightarrow s=\frac{28.7^2-0^2}{2\times 8.68}\\\Rightarrow s=47.5\ m](https://tex.z-dn.net/?f=v%5E2-u%5E2%3D2as%5C%5C%5CRightarrow%20s%3D%5Cfrac%7Bv%5E2-u%5E2%7D%7B2a%7D%5C%5C%5CRightarrow%20s%3D%5Cfrac%7B28.7%5E2-0%5E2%7D%7B2%5Ctimes%208.68%7D%5C%5C%5CRightarrow%20s%3D47.5%5C%20m)
It travels 47.5 m in that time
4) When s = 120 m
![s=ut+\frac{1}{2}at^2\\\Rightarrow 120=0\times t+\frac{1}{2}\times 8.68\times t^2\\\Rightarrow t=\sqrt{\frac{120\times 2}{8.68}}\\\Rightarrow t=5.26\ s](https://tex.z-dn.net/?f=s%3Dut%2B%5Cfrac%7B1%7D%7B2%7Dat%5E2%5C%5C%5CRightarrow%20120%3D0%5Ctimes%20t%2B%5Cfrac%7B1%7D%7B2%7D%5Ctimes%208.68%5Ctimes%20t%5E2%5C%5C%5CRightarrow%20t%3D%5Csqrt%7B%5Cfrac%7B120%5Ctimes%202%7D%7B8.68%7D%7D%5C%5C%5CRightarrow%20t%3D5.26%5C%20s)
The time it takes the cheetah to reach a rabbit is 120 m is 5.26 seconds
C. A complete revolution is 360 degree. two revolution is 720.
Explanation:
Calculate position vectors in a multidimensional displacement problem. Solve for the displacement in two or three dimensions. Calculate the velocity vector