# Accelerating fluid filled container [closed]

A container filled with fluid is accelerating initially with a1 and instantly changes to a2 (a2 < a1). What would happen to the fluid in the container.

My thoughts on this - If the velocity of the system is v1 when the acceleration changes to a2. The fluid will, at that instant, have a velocity of v1 while container accelerates (with an accleration a2) to v2 (v2>v1) The fluid in the container is moving backwards relative to the container. So, it would splash against the back wall of the container. Is this logically accurate or am I missing something.

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## closed as off-topic by Emilio Pisanty, akhmeteli, Manishearth♦Sep 8 '13 at 8:27

This question appears to be off-topic. The users who voted to close gave this specific reason:

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Please note that Homework questions are supposed to supposed to show more effort. For more details, please see the Homework Policy. – centralcharge Sep 4 '13 at 15:56
A homework question doesn't mean Real homework : ) Read the policy . – centralcharge Sep 4 '13 at 16:02
@udiboy: I think this is clearly homework(-like). – centralcharge Sep 4 '13 at 16:30

The container will not suddenly accelerate to $v_2$. When you suddenly change the acceleration to $a_2$, you are not providing an impulse to the container, so the velocity of the container just after the change will still be $v_1$ and not suddenly accelerate to $v_2$.
The velocity of the container will increase now too but by rate $a_2$ and not $a_1$(Note that it was increasing before the change too, due to acceleration $a_1$, in case you missed that). The water in the container will also accelerate by $a_2$, and you you won't experience a sudden splash effect.
When you change from $a_1$ to $a_2$, the equilibrium position changes its inclination $\theta$, so the fluid level starts oscillating about this level.
If you decrease acceleration(or provide negative acceleration), the inclination of the equilibrium position $\theta$ decreases, so the water level will also try to increase its inclination. In effect, it will look like the water is lunging forward, and splashing into the forward wall. That's basically what inertia predicts. – udiboy1209 Sep 4 '13 at 17:03