2. A 10 kg ball is rolled down a rail from a height of 20 m. What is the velocity at the bottom of the rail? Ignore friction.

19.8m/s

Explanation:

Given parameters:

Mass of the ball  = 10kg

Height of the rail  = 20m

Unknown:

Velocity at the bottom of the rail  = ?

Solution:

The velocity at the bottom of the rail is its final velocity.

Using the appropriate motion equation, we can find this parameter;

   V²   = U²  + 2gH

V is the final velocity

U is the initial velocity

g is the acceleration due to gravity

H is the height

  the ball was rolled from rest, U  = 0

  V²  = O²  + 2 x 9.8 x 20

 V  = 19.8m/s

a  solution  is always transparent, light passes through with no scattering from solute particles which are molecule in size. the  solution  is homogeneous and does not settle out. a colloid is intermediate between asolution  and a  suspension. while asuspension  will separate out a colloid will not.