Answer:
a) One-ninth the force acting on object A.
Explanation:
First, we derive an expression for the centripetal force acting on both objects.
For object A, centripetal force is:
For object B, centripetal force is:
We are given that they have the same mass and they move in circles of the same radius.
If object A completes three times as many rotations as object B, then, object must have 3 times the speed of object B.
Hence:
Therefore, 
becomes:
=> 
Therefore, the net centripetal force acting on object B is one-ninth of the force acting on object A.
A whole sentence includes a subject and a predicate
Answer:
Buffers
Explanation:
A buffer solution is a solution containing weak acids and their salts or weak bases and their salts.
A buffer solution is an equilibrium system that resists changes in pH or pOH when a small amount of an acid or base is added hence it is a solution of fairly constant pH value.
The given question is incomplete. The complete question is as follows.
A box of oranges which weighs 83 N is being pushed across a horizontal floor. As it moves, it is slowing at a constant rate of 0.90 m/s each second. The push force has a horizontal component of 20 N and a vertical component of 25 N downward. Calculate the coefficient of kinetic friction between the box and the floor.
Explanation:
The given data is as follows.
= 20 N, 
= 25 N, a = -0.9 
W = 83 N
m = 
= 8.46
Now, we will balance the forces along the y-component as follows.
N = W +
= 83 + 25 = 108 N
Now, balancing the forces along the x component as follows.
= ma
= 7.614 N
Also, we know that relation between force and coefficient of friction is as follows.
= 
= 0.0705
Thus, we can conclude that the coefficient of kinetic friction between the box and the floor is 0.0705.
