Part 1
If water does not spill at the top point of the circular motion then for the minimum speed condition we can say normal force will be zero at the top position



given that
R = 1 m
g = 9.8 m/s^2
now from above equation we have

Part b)
for minimum value of angular speed we will have



The key principle is that crank length, just like frame size, should be proportional to the rider height and then modified to what fits the individual. There are 4 charts, two for the upright position and two for the aero position, depending upon how you race.
Formulae for Kinetic energy is:
Kinetic Energy= 1/2xmassx(velocity)^2
For comparison we need to have same units,thus we convert 10g into Kg.
10g/1000=0.01Kg
Input the value of bullet in the formulae;
Kinetic Energy= 1/2x0.01kgx(400)^2
K.E=800J
Input value of the ball:
Kinetic Energy=1/2x80kgx(6.5)^2
K.E=1690J
Which means that th Energy of the ball is more than the bullet.
Both, there are two different types of molecules to distinguish that
Answer:
(a) 30 m/sec
(b) -50 m/sec
Explanation:
We have given initial velocity of ball u = 50 m/sec
Acceleration due to gravity 
(a) Time t = 2 sec
Now according to first equation of v = u-gt
So v=50-10×2=30 m/sec
(b) Time t = 10 sec
Now according to first equation of motion
So final velocity v = u-gt = 50-10×10 =-50 m/sec