This tricky question! (1 Viewer)

klee98

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This question is taunting me, i chose the blue one.
I know the question looks pretty darn obvious what it wants, but the way it was phrased though!!!
Here's my POV: Draw the magnitude of a ball dropped in a trolley by a scientist who's in the trolley relative to the scientist. Plus, its travelling in uniform acceleration, so its an inertial frame, hence vertical.

But the answer says otherwise. Am i reading it wrong??

 
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turntaker

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This question is taunting me, i chose the blue one.
I know the question looks pretty darn obvious what it wants, but the way it was phrased though!!!
Here's my POV: Draw the magnitude of a ball dropped in a trolley by a scientist who's in the trolley relative to the scientist
(They are all in the trolley!!)
But the answer says otherwise. Am i reading it wrong??

Lol doing physics at 1:30am?
Gg

Anyway, this is pretty basic. (Maybe you need sleep)

The scientist in the trolley which means he is in a inertial frame of references (where you are traveling in uniform motion )
Laws of physics would be same in the trolley so the ball will drop as normal.
 

klee98

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OMG yes, i do need sleep!!
i thought uniform acceleration = uniform velocity :spzz:
 

turntaker

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OMG yes, i do need sleep!!
i thought uniform acceleration = uniform velocity :spzz:
Oh wait. I thought it said uniform speed and not uniform acceleration.

I need sleep too

This changes the answer. The ball doesn't go straight down.
The red path is the correct answer
 

Parvee

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uhm its not an inertial frame of reference if its accelerating
 

Parvee

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and since its accelerating it will be the red one
 

Crisium

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Ok so as the acceleration is increasing at a steady rate this would mean that the scientist is in a non-inertial frame of reference.

Therefore the ball will follow a trajectory in an opposite direction to that of the direction of travel (i.e. Since it is travelling to the right, the ball will follow a trajectory to the left).

Hope this makes sense
 

Librah

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Ok so as the acceleration is increasing at a steady rate this would mean that the scientist is in a non-inertial frame of reference.

Therefore the ball will follow a trajectory in an opposite direction to that of the direction of travel (i.e. Since it is travelling to the right, the ball will follow a trajectory to the left).

Hope this makes sense
Dunno if you worded this weirdly or not, but bolded part isn't always true. In a decelerating vehicle the ball will appear to move forward.
 

anomalousdecay

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The scientist experiences a force which allows him to accelerate with the trolley (this force comes from the scientists friction against the trolley from his feet). The ball in his hand also experiences this force. Once the ball is dropped, the only force acting on it is that of gravity. Hence the scientist, being in a non-inertial frame of reference relative to the ball as he is experiencing a force while the ball is not, will observe the ball following the red path.
 

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