Answer:
2,158N
Explanation:
According to the second newtons law of motion, Force(F) = mass(m) × acceleration (a)... 1
Given mass to be 800kg.
We need to get the acceleration of the body using one of the equations of motion.
v²= u²+2as ... (2)where;
v = final velocity = 50km/hr
u = initial velocity = 20km/hr
a is the acceleration
s is the distance covered by the boat = 30m
Converting 50km/hr and 20km/hr to m/s, this gives us
50km×1000m/1hr×3600s
= 50000/3600
= 13.9m/s
Similarly,
20km/hr = 20000m/3600s
= 5.6m/s
Substituting this values into the equation 2 to get acceleration, we have
13.9²= 5.6²+2a(30)
193.21 = 31.36+60a
60a = 193.21-31.36
60a = 161.85
a = 2.69m/s²
To get the force on the both we substitute the value of mass and acceleration in equation 1
F =ma
F = 800×2.69
F= 2,158N
Therefore the force of friction on the boat is 2,158N
