Answer:0.69
Explanation:
Coefficient of kinetic friction=f/R=61.8/90=0.69
Answer:
The force on the ball is the same
Answer:
They have same density
Explanation:
The density of an object is defined as

where
m is the mass of the object
V is its volume
Let's call
and
the mass and the volume of ball C, respectively. Therefore, the density of ball C is:

We know that the volume of ball C is 3 times the volume of ball D, so

And we also know that ball D has 1/3 the mass of ball C:

So, the density of ball D is:

Therefore, the two balls have same density.
Answer:
I = 12 A
Explanation:
For this exercise we use the relationship that voltage is proportional to the product of current and resistance
V = I R
I = V / R
let's calculate
I = 120/10
I = 12 A
Answer:
the correct one is 2. the equipotential lines must be closer together where the field has more intensity
Explanation:
The equipotential line concept is a line or surface where a test charge can move without doing work, therefore the potential in this line is constant and they are perpendicular to the electric field lines.
In this exercise we have a charge and a series of equipotential lines, if this is a point charge the lines are circles around the charge, where the potential is given by
V = k q / r
also the electric field and the electuary potential are related
E =
therefore the equipotential lines must be closer together where the field has more intensity
When checking the answers, the correct one is 2