Changning velocity, check please

  • Thread starter Thread starter UrbanXrisis
  • Start date Start date
  • Tags Tags
    Velocity
AI Thread Summary
The discussion focuses on understanding changes in velocity through directional arrows representing motion over equal time frames. It confirms that if an object changes direction, the arrow indicating the change in velocity would point opposite to the initial direction. When discussing constant velocity, if an object moves from east to south-west, the change in velocity arrow would not point directly down but at an angle towards the west side of south. The conversation emphasizes the importance of correctly interpreting the direction and magnitude of velocity changes. Overall, the participants clarify the relationship between direction, velocity, and the resulting changes in motion.
UrbanXrisis
Messages
1,192
Reaction score
1
changing velocity, check please

The arrows indicate the velocity.

This is the object's motion in three equal time frames.

0---->...0-->...0

The arrow that shows the direction of the change in velocity would have to be: <--

correct?

What if the velocity was constant and the object went from 0----> to pointing south-west in the next time frame? Then the magnitude of the arrow that shows the direction of the change in velocity would be down correct?
 
Last edited:
Physics news on Phys.org
First part seems ok.

Initially, the object is pointing east in the second problem. If the object were to then point south-west in the next time frame, there would have to be something that causes it to change from east to west. Thus it would not point directly downwards, but at an angle towards the west side of south.
 
Sorry, bad wording, I mean south east
 
Oh, then yeah, you're right.
 

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Similar threads

Ambiguous question on momentum and how it works...
Replies
13
Views
1K
Circular motion doubt: Angular velocity vector for general planar motion about a point in the plane
Replies
6
Views
750
Projectile Motion on an Incline
Replies
6
Views
2K
Can Two Particles Have Multiple Collisions in a Single Interaction?
Replies
17
Views
1K
Force analysis of a spring-bob system
Replies
2
Views
648
Confused about direction of electric field
Replies
7
Views
3K
Is My Approach to Calculating Relative Velocity Correct?
Replies
20
Views
2K
Calculate Distance Traveled: Instantaneous vs. Average Velocity
Replies
5
Views
2K
Relation between Friction, Velocity, and Acceleration
Replies
16
Views
984
A or B? Increase in Velocity Backwards & Acceleration Forward
Replies
19
Views
2K

Hot Threads

Recent Insights

Back
Top