Answer:
, 
Explanation:
The situation can be modelled by applying the Principle of Angular Momentum Conservation:

The final angular speed is:



The tangential velocities of the wheel and the clay are, respectively:




The characteristics of the speed of the traveling waves allows to find the result for the tension in the string is:
T = 10 N
The speed of a wave on a string is given by the relationship.
v =
Where v es the velocty, t is the tension ang μ is the lineal density.
They indicate that the length of the string is L = 2.28 m and the pulse makes 4 trips in a time of t = 0.849 s, since the speed of the pulse in the string is constant, we can use the uniform motion ratio, where the distance traveled e 4 L
v =
v =
v =
v = 10.7 m / s
Let's find the linear density of the string, which is the length of the mass divided by its mass.
μ =
μ = 8.77 10⁻² kg / m
The tension is:
T = v² μ
Let's calculate
T = 10.7² 8.77 10⁻²
T = 1 0 N
In conclusion using the characteristics of the velocity of the traveling waves we can find the result for the tension in the string is:
T = 10 N
Learn more here: brainly.com/question/12545155
As per kinematics equation we know that
final speed of the car = 0 m/s
initial speed is given as 30 m/s
distance moved = 100 m
now we have



now braking force is given as

now for mass we know that the weight of car is

so mass of car is

now we have

Part b)
Again we have
final speed of the car = 0 m/s
initial speed is given as 30 m/s
distance moved = 10 m
now we have



now braking force is given as

mass of car is

now we have
