<span> For any body to move in a circle it requires the centripetal force (mv^2)/r.
In this case a ball is moving in a vertical circle swung by a mass less cord.
At the top of its arc if we draw its free body diagram and equate the forces in radial
direction to the centripetal force we get it as T +mg =(mv^2)/r
T is tension in cord
m is mass of ball
r is length of cord (radius of the vertical circle)
To get the minimum value of velocity the LHS should be minimum. This is possible when T = 0. So
minimum speed of ball v at top =sqrtr(rg)=sqrt(1.1*9.81) = 3.285 m/s
In the second case the speed of ball at top = (2*3.285) =6.57 m/s
Let us take the lowest point of the vertical circle as reference for potential energy and apllying the conservation of energy equation between top & bottom
we get velocity at bottom as 9.3m/s.
Now by drawing the free body diagram of the ball at the bottom and equating the net radial force to the centripetal force
T-mg=(mv^2)/r
We get tension in cord T=13.27 N</span>
Answer:

Explanation:
We know that the frequency of the nth harmonic is given by
, where
is the fundamental harmonic. Since we have the values of two consecutive frequencies, we can do:

Which for our values means (we do not need the value of <em>n</em>, that is, which harmonics are the frequencies given):

Now we turn to the formula for the vibration frequency of a string (for the fundamental harmonic):

So the tension is:

Which for our values is:

I'm not that smart but I think it is c I really hope It helps
S orbital.
Group 1 elements have a general configuration
, where n represents the highest occupied Principal Energy Level. For example, Lithium has the valence configuration
whereas Cesium has
. Both of them belong to Group 1 of Periodic Table.
Group 2 elements have a general configuration of
. For example, Magnesium has
as its outer shell configuration while Strontium has the same as
.
We see that in both the cases, the outermost S orbital is being filled.
When somebody hands you a Celsius°, it's easy to find the equivalent Fahrenheit°.
Fahrenheit° = (1.8 · Celsius°) + 32° .
So 100°C works out to 212°F.
It's also easy to find the equivalent Kelvin. Just add 273.15 to the Celsius.
So now you can see that 100°C is equal to A and D,
and it's less than B .
The only one it's greater than is C .