Here's a question, today I had on my test

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The discussion revolves around the behavior of an object rotating clockwise in a vertical circle and the corresponding tensions in the string at different points. The participant provided answers for the object's speed at various points, suggesting maximum speed at the top, slowing down due to gravity, and other speed states. Feedback indicates that the velocity cannot be zero at certain points, as centripetal acceleration must be maintained. The majority of the participant's answers were confirmed as correct, highlighting the importance of understanding forces in circular motion. Overall, the conversation emphasizes the need for clarity on the physics concepts involved.
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You fill in with a, b, c, d, e, or f. It can be more than 1.
The image is in the attachment

a. speed up
b. slow down
c. constant speed
d. maximum speed
e. minimum speed
f. speed is zero

What does the object do at each point if it is rotating clockwise in a vertical circle?

Here's what I put.

1. d
2. b, because of gravity
3. e, f
4. a

referring to the circle in the attachment

6. The tension in the string at the bottom of the circle equals.
a. mg - Fc
b. Fc - mg
c. mg + Fc
d. Fc
e. mg

7. The tension in the string at the top of the circle equals
a. mg - Fc
b. Fc - mg
c. mg + Fc
d. Fc
e. mg

6 -> c 7 -> b

Anyway that's what I put, but I'd like to know other people's opinions to know if I got it right for sure.
 

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Your first answer seems to be correct. I'm not an expert in physics, but it looks good to me.
Forgive me if this is an ignorant question, but what does the "string" refer to? Is it referring to the circle itself? Is the object attached to a string of some sort?
 
FrostScYthe said:
You fill in with a, b, c, d, e, or f. It can be more than 1.
The image is in the attachment

a. speed up
b. slow down
c. constant speed
d. maximum speed
e. minimum speed
f. speed is zero

What does the object do at each point if it is rotating clockwise in a vertical circle?

Here's what I put.

1. d
2. b, because of gravity
3. e, f
4. a

referring to the circle in the attachment

6. The tension in the string at the bottom of the circle equals.
a. mg - Fc
b. Fc - mg
c. mg + Fc
d. Fc
e. mg

7. The tension in the string at the top of the circle equals
a. mg - Fc
b. Fc - mg
c. mg + Fc
d. Fc
e. mg

6 -> c 7 -> b

Anyway that's what I put, but I'd like to know other people's opinions to know if I got it right for sure.


#3 should just be e. THe velocity cannot be zero there because a_{c} = \frac{v^2}{r} And a_c must be greater than or equal to g for the object to not fall and keep swinging.

All your other answers were correct.
 
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