Lunar Manatee
- 16
- 10
- Homework Statement
- A force F acts on a body of mass 1kg which moves from rest in a straight line starting from the origin point "O". If F=5x+6 where x is its displacement from the origin measured in metre, F in newton, then its velocity where r=4m (editor's note: that's the position vector) is ... m/sec
- Relevant Equations
- F=ma
a=vdv/dx
the attempt is visible in the image. my question is more... pedantic (?). if the initial conditions are to be taken into account, v_0=0, x_0=0 and F_0=+6, then isn't the velocity supposed to be v=+8sqrt(2)? or am I grasping at straws here.
my thought is, if the force is acting in the positive direction, then the acceleration is also acting in that positive direction, which means the velocity increases in that positive direction too (from 0) which should mean it's only larger than or equal to 0 on the interval t belongs to [0,+inf[
Model Answer says it's (c). I am just having trouble supporting either (c) or (a) as a valid answer.
Edit (1): I think I just realised what the flaw in my logic was; I appreciate the replies if they do come in! I hope they help cement more less-flawed logic in my brain for later use.
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