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Physics question resultant forces

Hi i really don’t get resultant forces and how to work them out? I need help on this question below please? I don’t get how to work out the direction, I’m getting a b and d as correct so im definitely doing something wrong.
Here is the question: https://app.gemoo.com/share/image-annotation/587392790404329472?codeId=M0GeqeBE2RJXY&origin=imageurlgenerator
Thank you!
Original post by anonymous294
Hi i really don’t get resultant forces and how to work them out? I need help on this question below please? I don’t get how to work out the direction, I’m getting a b and d as correct so im definitely doing something wrong.
Here is the question: https://app.gemoo.com/share/image-annotation/587392790404329472?codeId=M0GeqeBE2RJXY&origin=imageurlgenerator
Thank you!


Did you post the correct question as you asked for resultant forces while the question asked for relative velocity?
Although finding resultant force and relative velocity has a similar technique, they are still not the same. :smile:
Reply 2
Original post by Eimmanuel
Did you post the correct question as you asked for resultant forces while the question asked for relative velocity?
Although finding resultant force and relative velocity has a similar technique, they are still not the same. :smile:

Sorry yes, it is relative velocity, I don’t get how to calculate it using vectors? Thanks!
Original post by anonymous294
Sorry yes, it is relative velocity, I don’t get how to calculate it using vectors? Thanks!

I am sorry for the late reply. If you still need help, see below.

Before reading the following explanation, it would be good to read the info in this link first to understand how the notation works.
https://openstax.org/books/university-physics-volume-1/pages/4-5-relative-motion-in-one-and-two-dimensions
Understand mainly equation 4.33 in the link.

The first thing is to identify the given info using the frame of reference:
“An aeroplane can fly at a velocity X when moving through still air” means that X is the velocity of the aeroplane relative to the air or Vplane/air.
“When flying in wind the aeroplane’s velocity relative to the ground is Y” means that Y is the velocity of the aeroplane relative to the ground or Vplane/ground.
W is the velocity of air relative to the ground or Vair/ground.
Using the ordering notation that you have known from the link, we write
Vair/ground = Vair/plane + Vplane/ground
I would let you fill in X, Y and W, once you have placed them in the correct position in the above equation, you can choose the vector diagram to describe the addition or subtraction of vectors.

PS: I use a backlash to separate the words but the ordering of the subscripts remains unchanged.

Spoiler

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