Answer:
b) using an indicator to measure the hydrogen ion concentration of a solution
Answer:
The ratio of kinetic energies of 5 kg object to 20 kg object is 1:1.
Explanation:
Kinetic energy is defined as energy possessed by an object due to its motion.It is calculated by:

Kinetic energy of the 5 kg object.
Mass of object,m = 5 kg
Velocity of an object = v

Kinetic energy of the 20 kg object.
Mass of object,m' = 20 kg
Velocity of an object = v'

The ratio of the kinetic energy of the 5 kilogram object to the kinetic energy of the 20-kilogram object:

Given that, v = 2v'

The ratio of kinetic energies of 5 kg object to 20 kg object is 1:1.
the speed of the ball before it reaches the pool of water would be 9.91 m/s.
Answer:
Approximately
. (Assuming that
, and that the tabletop is level.)
Explanation:
Weight of the book:
.
If the tabletop is level, the normal force on the book will be equal (in magnitude) to weight of the book. Hence,
.
As a side note, the
and
on this book are not equal- these two forces are equal in size but point in the opposite directions.
When the book is moving, the friction
on it will be equal to
, the coefficient of kinetic friction, times
, the normal force that's acting on it.
That is:
.
Friction acts in the opposite direction of the object's motion. The friction here should act in the opposite direction of that
applied force. The net force on the book shall be:
.
Apply Newton's Second Law to find the acceleration of this book:
.
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