(a) Let
be the maximum linear speed with which the ball can move in a circle without breaking the cord. Its centripetal/radial acceleration has magnitude

where
is the radius of the circle.
The tension in the cord is what makes the ball move in its plane. By Newton's second law, the maximum net force on it is

so that

Solve for
:

(b) The net force equation in part (a) leads us to the relation

so that
is directly proportional to the square root of
. As the radius
increases, the maximum linear speed
will also increase, so the cord is less likely to break if we keep up the same speed.
Answer:
The temperature of the core raises by
every second.
Explanation:
Since the average specific heat of the reactor core is 0.3349 kJ/kgC
It means that we require 0.3349 kJ of heat to raise the temperature of 1 kg of core material by 1 degree Celsius
Thus reactor core whose mass is
will require

energy to raise it's temperature by 1 degree Celsius in 1 second
Hence by the concept of proportionately we can infer 150 MW of power will increase the temperature by
Electromagnets can be turned off, this makes it easier to release things from the magnetic field.
Hope this helps :)
Incompressible. Compressibility is determine by the amount of space between particles in each state.
The speed increases, because as the angle increases (the wing slants up more steeply), the air has to go farther to get over the wing.