Answer:
0.39
Explanation:
distance from the center (r) = 32 cm = 0.32 m
speed of the coin (v) = 110 cm/s = 1.1 m/s
acceleration due to gravity (g) = 980 m/s^{2} = 9.8 m/s^{2}
find the coefficient of static friction (k) between the coin and the turn table
frictional force = kmg
before the table begins to move, the frictional force balances the centripetal force (
)
therefore
frictional force = centripetal force
kmg = 
kg = 
k =
÷ g
k =
÷ 9.8 = 0.39
Answer:
Having a bigger angle above the horizontal
Explanation:
Applying the energy conservation theorem:

The kinetic energy is reduced because of the work done by the friction force.
The friction force is given by:

so the friction force depends on the Normal force, because the slide has an angle the normal force is given by:

So when the angle of the slide is bigger, the friction force decreases, for example:
for 45 degrees:

for 75 degrees:

as you can see if the angle is bigger above the horizontal, the friction force is reduced and so the work done by that force. We didn't have to change the height of the slide, so the potential gravitational energy remains the same.
This
is
true
Electromagnetic waves travel fastest through vacuum
In the circuit outside of the battery the electrons have to expend all of their energy on the internal resistance of the battery which causes heating