Circular Motion and Centripetal Force

AI Thread Summary
The discussion revolves around understanding concepts of circular motion and centripetal force through a series of practice questions. Key points include the direction of acceleration for a test mass in circular motion, which is towards the center of the circle, and the necessary measurements to determine centripetal acceleration, such as mass, velocity, and radius. Participants emphasize the importance of engaging with the material rather than simply seeking answers, suggesting that educated guesses can lead to better understanding. The force maintaining circular motion is identified as the tension in the string or the weight of a hanging mass. Overall, the conversation encourages active participation in learning physics concepts.
gavrir
Messages
12
Reaction score
0
Hey guys i was taking some practice excercises and was wondering if someone could give me the answers to the following:

1.The following questions are about this experiment in which a test-mass moves in a horizontal circle at constant speed. What is the direction of the test-mass acceleration?

a. Downward
b. In the direction of velocity.
c. Towards the center of the circle.
d. Away from the center of the circle.
e. Upward.
f. Opposite the direction of the velocity.


2.What measurements will be made to determine the magnitude of the test-mass centripetal acceleration?
A. The test-mass mass
B. The test-mass velocity
C. The radius of the orbit
D. The weight of the hanging mass
E. The spring constant
F. The period of the orbital motion

1. B, C
2. A, D
3. C, F
4. B, E
5. A, B, D


3.A particle in uniform circular motion requires a net force acting in what direction?

a. Downward
b. Opposite the direction of the velocity.
c. Away from the center of the circle.
d. In the direction of velocity.
e. Towards the center of the circle.
f. Upward.


4. What supplies the force that keeps the test mass moving in uniform circular motion?

a. The string attached to the mass.
b. The spring that pulls on the string attached to the mass.
c. The weight of the hanging mass.
d. The string from the test-mass riser holding up the mass.
e. You -- as you keep the apparatus spinning.

5.How will the centripetal force be experimentally determined?

a. From the acceleration and mass of the test mass
b. From the weight of the hanging mass.
c. From the velocity, radius, and mass of the test mass.
d. The centripetal force is not determined in this experiment.
 
Physics news on Phys.org
gavrir said:
Hey guys i was taking some practice excercises and was wondering if someone could give me the answers to the following:

1.The following questions are about this experiment in which a test-mass moves in a horizontal circle at constant speed. What is the direction of the test-mass acceleration?

a. Downward
b. In the direction of velocity.
c. Towards the center of the circle.
d. Away from the center of the circle.
e. Upward.
f. Opposite the direction of the velocity.


2.What measurements will be made to determine the magnitude of the test-mass centripetal acceleration?
A. The test-mass mass
B. The test-mass velocity
C. The radius of the orbit
D. The weight of the hanging mass
E. The spring constant
F. The period of the orbital motion

1. B, C
2. A, D
3. C, F
4. B, E
5. A, B, D


3.A particle in uniform circular motion requires a net force acting in what direction?

a. Downward
b. Opposite the direction of the velocity.
c. Away from the center of the circle.
d. In the direction of velocity.
e. Towards the center of the circle.
f. Upward.


4. What supplies the force that keeps the test mass moving in uniform circular motion?

a. The string attached to the mass.
b. The spring that pulls on the string attached to the mass.
c. The weight of the hanging mass.
d. The string from the test-mass riser holding up the mass.
e. You -- as you keep the apparatus spinning.

5.How will the centripetal force be experimentally determined?

a. From the acceleration and mass of the test mass
b. From the weight of the hanging mass.
c. From the velocity, radius, and mass of the test mass.
d. The centripetal force is not determined in this experiment.

This question belongs in the Homework & Coursework Questions section at https://www.physicsforums.com/forumdisplay.php?f=152

I also believe that it is against forum policy not to give answer's to questions for which the person asking the question has not taken any effort to answer the question themselves. Therefore I recommend that you take some educated guesses to the questions above or if you are unable to then perhaps tell us where you are stumped and we can help you from there. Good luck!

Best wishes

Pete
 
I know the answers for 3,4,5 are c,a and b b ut i don't understand the first 2..Thanks
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top