Physics (Net Forces/Newton's laws)

[austin1250]

Alright well I have 2 questions I am stuck on.

first is:

Four forces act on a hot-air balloon, shown from the side in the figure below. Find the magnitude and direction of the resultant force on the balloon if F1 = 4600 N, F2 = 1250 N, F3 = 1000 N, and F4 = 4200 N.


F1 is pointing up, F4 is pointing down, F2 is pointing left and F3 is pointing right.

It asks for the force in N and at what degree clockwise from F2.

I got the force to be 300 N northward, and 250 N to the lef (west). I don't get how to get the Degree(direction) clockwise from F2. Any help?



And the other problem is:
An 1750 kg car is moving to the right at a constant speed of 1.92 m/s.

(a) What is the net force on the car?
_______ N to the right
(b) What would be the net force on the car if it were moving to the left?
_______ N to the left

I don't really know what to do here. i just used F=MA but it was wrong. i don't think 1.92 m/s can be used since it isn't acceleration but i don't really know what to do. any help?

 

[PhanthomJay]

Alright well I have 2 questions I am stuck on.

first is:

Four forces act on a hot-air balloon, shown from the side in the figure below. Find the magnitude and direction of the resultant force on the balloon if F1 = 4600 N, F2 = 1250 N, F3 = 1000 N, and F4 = 4200 N.


F1 is pointing up, F4 is pointing down, F2 is pointing left and F3 is pointing right.

It asks for the force in N and at what degree clockwise from F2.

I got the force to be 300 N 4600-4200 = 400[/color]northward, and 250 N to the lef (west). I don't get how to get the Degree(direction) clockwise from F2. Any help?

You have the components of the resultant, can you find the magnitude of the resultant using the Pythagorean Theorem? Can you find the angle of the resultant using the trig properties of a right triangle?

And the other problem is:
An 1750 kg car is moving to the right at a constant speed of 1.92 m/s.

(a) What is the net force on the car?
_______ N to the right
(b) What would be the net force on the car if it were moving to the left?
_______ N to the left

I don't really know what to do here. i just used F=MA but it was wrong. i don't think 1.92 m/s can be used since it isn't acceleration but i don't really know what to do. any help?

You must use the acceleration. What is the car's acceleration if it is moving at constant speed?