Answer
given,
Tension of string is F
velocity is increased and the radius is not changed.
the string makes two complete revolutions every second
consider the centrifugal force acting on the stone
= 
now centrifugal force is balanced by tension
T =
From the above expression we can clearly see that tension is directly proportional to velocity and inversely proportional to radius.
When radius is not changing velocity is increasing means tension will also increase in the string.
To be effective, an exercise program must have an aerobic
form, portion for strength enhancement, and a stretching part. These three
things are essential because they each target specific improvements in your
body. For example, aerobics can help you maintain your body’s fitness or make
it better. This usually targets your heart rate and ensures that you burn fat
while doing so. Second is strength enhancement; this will make sure that your
body becomes better – not just in a feeble state. Lastly is stretching, your
muscles are like rubber bands. You cannot end or start your exercise program
without stretching simply because they can damage your muscles as well. Aside
from this, stretching can stop you from shocking your body into a physical
activity, which may cause you to lose consciousness or have undue stress and fatigue.
Answer:
O²⁻
Explanation:
Number of protons = 8
Number of neutrons = 9
Number of electrons = 10
What type of atom or ion is it = ?
Solution:
Protons are the positively charged particle in an atom
Neutrons do not carry any charges
Electrons are negatively charged particles
For this atom, the number of protons helps to identify what specie it is; so this is an oxygen atom.
Now,
Charge = Number of protons - Number of electrons
Charge = 8 - 10 = -2
The charge on the atom is -2 and so it is an oxygen ion with -2 charge
The ion is O²⁻
Answer:
sum of these two vectors is 6.06i+3.5j-3.5i+6.06j = 2.56i+9.56j
Explanation:
We have given first vector which has length of 7 units and makes an angle of 30° with positive x-axis
So x component of the vector 
y component of the vector 
So vector will be 6.06i+3.5j
Now other vector of length of 7 units and makes an angle of 120° with positive x-axis
So x component of vector 
y component of the vector 
Now sum of these two vectors is 6.06i+3.5j-3.5i+6.06j = 2.56i+9.56j
Answer:
a) 4
b) 2
c) 8
Explanation:
In a cubic lattice, each atom of the vertex is shared among other 8 unit cells, so the atoms on the vertex contribute to 1/8 to a given unit cell.
a) Ina face-centered cubic we have 8 atoms on the vertex and one in each face, which is shared with another unit cell, so it contribute to 1/2
Therefore, the total atoms are:
8*(1/8) + 6*(1/2) = 4
b) In the body centered cubic structure, the centered atom is not shared with another cell, therefore it contribute to 1 to the given cell:
The number of atoms per unit cel is:
8*(1/8) + 1 = 2
c) The diamond lattice is similar to the face-centered cubic lattice but it contains two identical atoms per lattice point.
Therefore it must contain twice atoms than the face-centered cubic lattice:
that is, it has 8 atoms per unit cell
