Answer:
2085.06N
2.47m/s
Explanation:
Question 1
Given parameters:
Mass of boat = 3460kg
Distance traveled by boat = 5250m
Time taken for travel = 2.20minutes.
Unknown:
Net force exerted = ?
Solution:
According to newton's second law of motion "the acceleration of a body is directly proportional to the force on it and inversely proportional to the mass of the body"
   a  = [tex]\frac{F}{m}[/tex]
F is the net force, a is the acceleration and m is the mass
Acceleration is the change in velocity of a body with time;
    a = [tex]\frac{V - U}{t}[/tex]
V is the final velocity
U is the initial velocity
t is the time taken
    since the boat starts from rest, initial velocity = 0
 Final velocity;
       V = [tex]\frac{displacement}{time}[/tex]
Now,
        F = ma
  In linear motion;
       s= ut + [tex]\frac{1}{2}[/tex] a t²
        t = 2.2min to seconds = 2.2 x 60 = 132s
s = distance covered
       5250 = 0 x 131  + [tex]\frac{1}{2}[/tex] x a x 132²
        5250 = 8712a
          a = 0.6m/s²
      Since  F = ma
        F = 3460 x 0.6 = 2085.06N
Question 2:
Given parameters:
Force = 2400N
time taken = 36s
Mass = 35000kg
Unknown:
Final velocity = ?
Solution:
 According to newton's second law;
       F = ma
   F is force
   m is the mass
   a is the acceleration
     a = [tex]\frac{V - U}{t}[/tex]
    V is final velocity
     U is initial velocity
     t is the time taken
Since U = 0;
     a = [tex]\frac{V}{t}[/tex]
     F = m x [tex]\frac{V}{t}[/tex]
  Â
    2400 = 35000 x [tex]\frac{V}{36}[/tex]
      V = 2.47m/s
