Year 11 motion/vector problem?

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SUMMARY

The discussion revolves around a Year 11 physics problem involving motion and vectors. A body with a mass of 5 kg is moving at a velocity of 28.3 m/s in a north-easterly direction, while experiencing a westerly wind force of 73.5 N. The correct change in momentum after 8 seconds is calculated to be 588 N·s directed east. The participant struggles with vector concepts and seeks clarification on how to properly represent and calculate the components of velocity and momentum.

PREREQUISITES
  • Understanding of Newton's second law (F = ma)
  • Basic knowledge of vector components and their representation
  • Familiarity with momentum calculations (p = mv)
  • Ability to perform trigonometric calculations for non-right triangles
NEXT STEPS
  • Study vector decomposition and how to resolve vectors into components
  • Learn about momentum and impulse in physics
  • Explore graphical methods for vector addition and subtraction
  • Review the principles of kinematics, particularly in two dimensions
USEFUL FOR

This discussion is beneficial for Year 11 physics students, educators teaching motion and vector concepts, and anyone looking to improve their understanding of momentum and forces in physics.

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Homework Statement


I'm really not good at motion. It just doesn't seem to come easily to me, which is kind of disapointing, because physics is my favourite subject.

Question: A body of mass 5kg is moving in a north easterly direction with a velocity of 28.3 m/s. If a westerly wind acts on it with a force of 73.5N what is the change in momentum after 8s.

Homework Equations


F = ma, a = v/s
?

The Attempt at a Solution


I figured i'd find the velocity of the force.
F = ma
73.5 = 5a
a= 14.7

a = v/t
v = 14.7 * 8
v = 117.6

difference in p = m(v-u)
p = 5(117.6-28.3)

But this doesn't give the right answer. The answer is 588 N s East.

I know i probably need to draw vectors and what not but the whole concept of vectors confuses me deeply. :(
Could you explain to me how the diagram would work? Would i need to use non-right trig? And also, what am i doing wrong?
I don't understand a lot of the concepts of vectors and motion, so try and explain it in the simplest way possible, because I am not great at this stuff.

Any help is appreciated. Thanks :)
 
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You need to think about velocity components for this one.

The change in velocity is in the east/west direction. So what was the initial east/west velocity component?

p.s. welcome to PF.
 

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