Magnitude and direction of Wind Force

AI Thread Summary
The discussion focuses on calculating the wind force acting on a boat given its mass, initial and final velocities, and the forces from an auxiliary engine and water resistance. The user attempts to resolve the forces into their components and apply Newton's second law, but struggles with isolating the wind force from the net forces. They calculate the resultant force from the auxiliary engine and water resistance but realize they need to separate the wind force for a complete solution. The conversation emphasizes the need to find both x and y components to determine the overall effect of the wind on the boat's motion. The user seeks guidance on the correct approach to isolate and calculate the wind force.
tryton
Messages
4
Reaction score
0

Homework Statement


1. Homework Statement
A 373-kg boat is sailing 13.0 ° north of east at a speed of 2.00 m/s. 32.0 s later, it is sailing 33.0 ° north of east at a speed of 3.90 m/s. During this time, three forces act on the boat: a 33.1-N force directed 13.0 ° north of east (due to an auxiliary engine), a 22.9-N force directed 13.0 ° south of west (resistance due to the water), and Fw(due to the wind). Find the (a) the magnitude and (b) direction of the force Fw. Express the direction as an angle with respect to due east.

Homework Equations


Force=ma
Kinematic equations

The Attempt at a Solution


33.1N-22.9N=10.2N Narrowed down the forces as these two are facing the same direction
M=373Kg
V0=2.0m/s
vx0=1.95m/s
vy0=.450m/s
v=3.9m/s
vx=3.27m/s
vy=2.13m/s
theta1=13degrees
theta2=33degrees

I am not sure where to go from here. What is missing is x,y,a, and Force of wind.
Can get x,y,a from breaking Force down into the x and y components and then use that to find F=ma for x=v0t+1/2at^2 but then I don't know if that is right and still don't know how to get the force of the wind...

Is that the right direction to go in at least?
Thanks for any help on this one.
 
Last edited:
Physics news on Phys.org
I think you are supposed to find the resultant force that the boat makes with the auxiliary engine and the water. Do you know how to add components and find the resultant vector?
 
I realized that part of the question didn't show up. I need to find the Fw, the Force of the wind.

I can add the two forces but I don't know how to separate out Fw.

so
Fa=Force auxiliary engine
Fax=22.1cos13=34.25
Fay=33.1sin13=7.45

Fwc=Force of watercurrent and wind
Fwcx=-29.9cos13=-29.1
Fwcy=-29.9sin13=-6.73

Added the Net Force is
Fx=5.12
Fy=.720

Then
F=ma
ax=5.12/373=.0137
ay=.720/373=.00193

a= square root of (.0137 ^2+.00193^2)=.0139

arctan(.00193/.0137)=8.006degrees

But then that is both water AND wind ...
and they just want the force of the wind.

x=V0t+1/2at^2
x= 2.0m/s * 32.0s + 2 * .0139m/s^2 * 32.0s^2
x=92.47m

Do I need to find Y as well? and then add x and y?
 
oh I am sorry. I didnt see the Fw part. Well, the next question is, what do you think, conceptually, the net force is going to be, if there is a net velocity of 3.9m/s during that instentaneous time at 32 seconds?
 
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Struggling to make relation between elastic force and height'
Hello guys this is what I tried so far. I used the UTS to calculate the force it needs when the rope tears. My idea was to make a relationship/ function that would give me the force depending on height. Yeah i couldnt find a way to solve it. I also thought about how I could use hooks law (how it was given to me in my script) with the thought of instead of having two part of a rope id have one singular rope from the middle to the top where I could find the difference in height. But the...
Back
Top