Answer:
t = 1.58 s
Explanation:
given,
Speed of ranger, v = 56 km/h
v = 56 x 0.278 = 15.57 m/s
distance, d = 65 m
deceleration,a = 3 m/s²
reaction time = ?
using stopping distance formula
![d = v. t + \dfrac{v^2}{2a}](https://tex.z-dn.net/?f=d%20%3D%20v.%20t%20%2B%20%5Cdfrac%7Bv%5E2%7D%7B2a%7D)
![t = \dfrac{d}{v} -\dfrac{v}{2a}](https://tex.z-dn.net/?f=t%20%3D%20%5Cdfrac%7Bd%7D%7Bv%7D%20-%5Cdfrac%7Bv%7D%7B2a%7D)
t is the reaction time
![t = \dfrac{65}{15.57} -\dfrac{15.57}{2\times 3}](https://tex.z-dn.net/?f=t%20%3D%20%5Cdfrac%7B65%7D%7B15.57%7D%20-%5Cdfrac%7B15.57%7D%7B2%5Ctimes%203%7D)
t = 1.58 s
hence, the reaction time of the ranger is equal to 1.58 s.
Answer:
D. The oxygen side is partially negative because electrons are pulled toward the oxygen side.
Explanation:
The water molecule is polar by the virtue of covalent bonds and the hydrogen bonds within and between its molecule.
The oxygen side is partially negative because the electrons are pulled toward the oxygen side.
Between oxygen and hydrogen that makes up the water molecule, oxygen is more electronegative.
An electronegative atom has more affinity for electrons. Since the electrons in the molecule of water is shared between hydrogen and oxygen, the more electronegative specie which is water draws the electron more to itself.
This leaves a net negative charge on the oxygen atom.
Beat frequency is given by the difference of two frequencies played together
![f_{beat} = |f_1 - f_2|](https://tex.z-dn.net/?f=f_%7Bbeat%7D%20%3D%20%7Cf_1%20-%20f_2%7C)
given that
![f_1 = 1560 Hz](https://tex.z-dn.net/?f=f_1%20%3D%201560%20Hz)
![f_2 = 1563 Hz](https://tex.z-dn.net/?f=f_2%20%3D%201563%20Hz)
Now
![f_{beat} = |1560- 1563| Hz](https://tex.z-dn.net/?f=f_%7Bbeat%7D%20%3D%20%7C1560-%201563%7C%20Hz)
![f_{beat} = 3 Hz](https://tex.z-dn.net/?f=f_%7Bbeat%7D%20%3D%203%20Hz)
The correct answer is B. Fuse.
Fuses were commonly used in houses up to recent ages, when circuit breakers became the more popular options, as they don't have to be changed every time they melt, since they don't melt.