Can't Check Your Work: Conceptual Problems in Physics

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The discussion revolves around conceptual problems in physics, focusing on the relationship between acceleration and velocity. It confirms that an object can indeed increase its speed even if the magnitude of its acceleration decreases. The motion of an object is described accurately in terms of its velocity being parallel, anti-parallel, or perpendicular to acceleration. The behavior of a coin thrown in a moving train is correctly noted as traveling with the train. Despite initial confidence in understanding the material, the user ultimately decided to drop the class, indicating a lack of assurance in their performance.
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1. Can an object increase its speed if the magnitude of the acceleration is decreasing?

I put yes because an object be accelerating at 50 m/s^2 and then decelerate to 40 m/s^2 but velocity would still increase.


2. Describe the motion of the object
V parallel to a
V anti-parallel to a
V perpendicular

I put that when V is parallel with a, it accelerates
When V is anti-parallel with a, it decelerates
When it's perpendicular, its at rest


3. Standing in a train, you throw a coin to the side, describe the motion of the coin.

I put that the coin will travel with the train and drop under where the person dropped the coin at.

4. When traveling down a flat road at a constant speed, do you feel lighter, heavier, or the same.
Going up a hill?
Going down a hill?

I put the same for the flat road, lighter going up a hill, and heavier going down.


Can anyone please check my work? I want to know how I did on an exam. Thank you.
 
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does anyone know the answer to any of these?

I have 2 hours to decide whether to drop my class or not
 
Jngo22 said:
1. Can an object increase its speed if the magnitude of the acceleration is decreasing?

I put yes because an object be accelerating at 50 m/s^2 and then decelerate to 40 m/s^2 but velocity would still increase.


2. Describe the motion of the object
V parallel to a
V anti-parallel to a
V perpendicular

I put that when V is parallel with a, it accelerates
When V is anti-parallel with a, it decelerates
When it's perpendicular, its at rest


3. Standing in a train, you throw a coin to the side, describe the motion of the coin.

I put that the coin will travel with the train and drop under where the person dropped the coin at.

4. When traveling down a flat road at a constant speed, do you feel lighter, heavier, or the same.
Going up a hill?
Going down a hill?

I put the same for the flat road, lighter going up a hill, and heavier going down.


Can anyone please check my work? I want to know how I did on an exam. Thank you.

Welcome to the PF. Mostly right answers, and good intuition. #2(c) could use some fixing, though.
 
Jngo22 said:
does anyone know the answer to any of these?

I have 2 hours to decide whether to drop my class or not

Don't drop it. You're doing fine.
 
thanks for the help, I really appreciate it

I dropped the class already though XD
 
Jngo22 said:
thanks for the help, I really appreciate it

I dropped the class already though XD

That's too bad, you sounded like you had a handle on the course material. Oh well, hopefully you take the course next term.
 
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