Question

A boat moves through the water with two forces acting on it. One is a 2000 N forward push by the water on the propeller, and the other is an 1800 N resistive force due to the water around the bow. a) What is the acceleration of the 1000 kg boat? (10 points) b) If it starts from rest, how far will the boat move in 10 sec.? (10 points) c) What will its velocity be at the end of that time?

Answer 1

Answer:

a). a=0.2 $\frac{m}{s^{2} }$

b). x=10m

c). v=2$\frac{m}{s}$

Explanation:

Force forward push = 2000N

Resistive force due water=1800N

Net force=2000N-1800N

Fn=200N

m=1000kg

t=10sec

a).

$F_{n} =m*a\\a=\frac{F_{n}}{m}\\ a=\frac{200N}{1000kg}\\ a=0.2 \frac{m}{s^{2} }$

b).

$x_{f}=x_{o}+ v_{o}*t+\frac{1}{2}*a*t^{2}\\x_{o}=0\\v_{o}=0\\x_{f}=\frac{1}{2}*a*t^{2}\\x_{f}=\frac{1}{2}*0.2*(10)^{2} \\x_{f}=10m$

c).

$v_{f}=v_{o}+a*t\\v_{o}=0\\v_{f}=a*t\\v_{f}=0.2\frac{m}{s^{2} }*10s\\v_{f}=2\frac{m}{s}$