Explanation:
Given that,
2 strings both vibrate at exactly 220 Hz. The frequency of sound wave depends on the tension in the strings.
The tension in one of them is then decreased sightly, then 
will decrese.
Beat frequency, 
So, the new frequency of the string is 217 Hz. Hence, this is the required solution.
Answer:
a. water
Explanation:
A buoy is a floating object that is used in the sea to locate some point or as a checkpoint. It stays at its designated position in the sea by means of an anchor chain. This chain is made short in length according to the water depth do the buoy can not deviate much from its position. The same mechanism can be applied to the metal ion. When a metal ion is formed it remains at its place, but the electrons are mobile and they travel when they get a medium. For example in circuits or from one atom to other. And for the case of buoy, the water serves as electrons as the water is moving in the medium. Hence, the second analogy will be:
electrons : water
So, the correct option is:
<u>a. water</u>
Answer:
2.7 Pizzas.
Explanation:
The power required to walk through 5km in 1 hour is 380W.
A watt is basically Jules per second, then we need to standardized this measurement to second.
5km/hr is equal to,
Walking by 2.5 hours is equal to a distance of,
The total energy required then would be,
Then we know that one pizza slice gives 
of energy, the total pizza needed are,
<em>Then you need to buy 3 pizza.</em>
Its just Calcium Flouride because as you can see it is an Ionic bond (Ca is metal and fl is a gas usually)
