Answer:
Vi = 32 [m/s]
Explanation:
In order to solve this problem we must use the following the two following kinematics equations.

The negative sign of the second term of the equation means that the velocity decreases, as indicated in the problem.
where:
Vf = final velocity = 8[m/s]
Vi = initial velocity [m/s]
a = acceleration = [m/s^2]
t = time = 5 [s]
Now replacing:
8 = Vi - 5*a
Vi = (8 + 5*a)
As we can see we have two unknowns the initial velocity and the acceleration, so we must use a second kinematics equation.

where:
d = distance = 100[m]
(8^2) = (8 + 5*a)^2 - (2*a*100)
64 = (64 + 80*a + 25*a^2) - 200*a
0 = 80*a - 200*a + 25*a^2
0 = - 120*a + 25*a^2
0 = 25*a(a - 4.8)
therefore:
a = 0 or a = 4.8 [m/s^2]
We choose the value of 4.8 as the acceleration value, since the zero value would not apply.
Returning to the first equation:
8 = Vi - (4.8*5)
Vi = 32 [m/s]
 
        
             
        
        
        
Hmmm...maybe it would be because since you're staying still then things appear to go by quickly.
        
             
        
        
        
The net force is 270 N
Explanation:
We can solve this problem by using Newton's second law, which states that the net force on an object is equal to the product between its mass and its acceleration:

where
F is the force
m is the mass
a is the acceleration
In this problem, we have
m = 90.0 kg

Substituting, we find the net force on the object:

Learn more about Newton's second law:
brainly.com/question/3820012
#LearnwithBrainly
 
        
             
        
        
        
This is a conservation of momentum problem! Here's how to do it:
 
        
             
        
        
        
Answer:
49N
Explanation:
F=ma
We know the mass is 5kg, and since the ball is suspended on one cable, the acceleration is g, 9.8m/s^2
F=5kg*9.8m/s^2
  = 49N
Hope this helps!