C. Both A. and B.
Explanation:
Statement A. Reducing the volume is true because of Boyle's law, which states that for a gas at fixed temperature, the pressure p and the volume V are inversely proportional:
![pV=const.](https://tex.z-dn.net/?f=pV%3Dconst.)
Therefore, when the volume V is reduced, the pressure p increases.
Statement B. Adding more gas is also true: in fact, if we add gas into the container, we will have more molecules of the gas hitting the wall of the container. But the pressure of a gas is exactly given by this: by the collision of the molecules against the wall of the container, so the more the molecules of gas, the greater the pressure.
Explanation:
A point on the rim of the wheel went from rest to 15 m/s so we can solve for the acceleration as
![v = v_0 + at \Rightarrow a = \dfrac{v}{t} = \dfrac{15\:\text{m/s}}{8.0\:\text{s}}](https://tex.z-dn.net/?f=v%20%3D%20v_0%20%2B%20at%20%5CRightarrow%20a%20%3D%20%5Cdfrac%7Bv%7D%7Bt%7D%20%3D%20%5Cdfrac%7B15%5C%3A%5Ctext%7Bm%2Fs%7D%7D%7B8.0%5C%3A%5Ctext%7Bs%7D%7D)
or
![a = 1.9\:\text{m/s}^2](https://tex.z-dn.net/?f=a%20%3D%201.9%5C%3A%5Ctext%7Bm%2Fs%7D%5E2)
We also know that the angular acceleration
is
![a = r\alpha \Rightarrow \alpha = \dfrac{a}{r}](https://tex.z-dn.net/?f=a%20%3D%20r%5Calpha%20%5CRightarrow%20%5Calpha%20%3D%20%5Cdfrac%7Ba%7D%7Br%7D)
Using r = 0.30 cm and a = 1.9 m/s^2, we get
![\alpha = \dfrac{a}{r} = \dfrac{1.9\:\text{m/s}^2}{0.30\:\text{m}}](https://tex.z-dn.net/?f=%5Calpha%20%3D%20%5Cdfrac%7Ba%7D%7Br%7D%20%20%3D%20%5Cdfrac%7B1.9%5C%3A%5Ctext%7Bm%2Fs%7D%5E2%7D%7B0.30%5C%3A%5Ctext%7Bm%7D%7D)
![\;\;\;\;=6.3\:\text{rad/s}^2](https://tex.z-dn.net/?f=%5C%3B%5C%3B%5C%3B%5C%3B%3D6.3%5C%3A%5Ctext%7Brad%2Fs%7D%5E2)
Answer:
By Factor of 4
Explanation:
The expression for centripetal acceleration is given as,
a = v²/r........... equation 1
Where a = centripetal acceleration, v = speed, r = radius of the circle.
Case 1
Given: v = 150 m/s, r = 500 m
Substitute into equation 1
a = 150²/500
a = 22500/500
a = 45 m/s².
Case 2
Given: v = 300 m/s, r = 500 m
Also substitute into equation 1
a = 300²/500
a = 180 m/s²
Factor of change of the acceleration = 180/45
Factor of change of the acceleration = 4.
Hence the acceleration will change by a factor of 4
We know average speed =total distance/time taken
So avg speed=(85+63)/(5+5)=14.8km/hr