You have to solve this by using the equations of motion:
u=3
v=0
s=2.5
a=?
v^2=u^2+2as
0=9+5s
Giving a=-1.8m/s^2
Then using the equation:
F=ma
F is the frictional force as there is no other force acting and its negative as its in the opposite direction to the direction of motion.
-F=25(-1.8)
F=45N
Then use the formula:
F=uR
Where u is the coefficient of friction, R is the normal force and F is the frictional force.
45=u(25g)
45=u(25*10)
Therefore, the coefficient of friction is 0.18
Hope that helps
Answer:
C. Supervising the game to make sure teams are playing fairly
Answer:
The angle from the vertical is 48.72°
Explanation:
Given :
Length of rope
m
Mass of man
Kg
Mass of car
Kg
Velocity of car

According to conservation law,
Potential energy of man is converted to kinetic energy of car moving,

We calculate height,

( ∵
)
m
This is the distance of the rope at the bottom,
So we take difference of it.
⇒ 
We can calculate angle between them,

48.72°
Therefore, the angle from the vertical is 48.72°
The correct answer for this question is this one:"D) The heavier ball will have a higher temperature because the change of temperature is inversely proportional to mass."<span>
</span>Hope this helps answer your question and have a nice day ahead.