How Does Angular Acceleration Affect Spacecraft and Clock Movements?

AI Thread Summary
The discussion revolves around calculating angular speed and acceleration for a spacecraft and a clock's hands. For the spacecraft, the initial angular speed should be determined based on the moon's orbit, and the final angular speed after 12 hours of constant angular acceleration is incorrectly calculated. The second problem involves the hour hand of a clock, where the angular acceleration is derived from the difference in angular speeds over time, but the initial and final speeds may have been misinterpreted. Participants emphasize the importance of correctly identifying initial conditions and converting units where necessary. Clarifications on these calculations are sought to ensure accuracy in the homework problems.
syncstarr
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The moon orbits Earth in 27.3 days. suppose a spacecraft leaves the moon and follows the same orbit as the moon. if the spacecraft has a constant angular acceleration of 1.0 X 10^ -10 rad/s 62 what is its angular speed after 12h of flight? (Hint: At take off the spaceship has the same angular speed as the moon)

MY ANSWER:
given: angular acceleration =1.0X 10^-10 rad/s^2
t=12hours w final=?

equation: w final = w initial + angular accelerationt
=0+1.0X 10^-10(12)
=1.2 X 10^-9 rad/sec^2
Is this correct?? is my work and answer correct??

2. Consider a common analog clock. at midnight the hour and minute hands coincide. then the minute haand begins to rotate away from the hour hand. suppose you adjust the clock by pushing the hour hand clockwise with a constant acceleration. after 60.0 min, the hour hand has the same angular speed as the minute hand. calculate the hour hands angular acceleration.

my answer/work:
givn:
angular acceleration=?
w initial =12
w finial=60.0
t=1
equation:
w final= w initiaila+(angular acceleration )(t)
60=12+ angular acceleration (1)
60-12= angular acceleration
48 rad/s

are these the correct work and answers to these two problems? if you know either or both please let me know by leaving me a comment! THANK YOU VERY MUCH FOR TAKING THE TIME TO READ THIS! i just want to check parts of my homework problems that i am unsure about. so if you can help me please do. THANKs
 
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First of all, I assume your post would have been answered earlier if you used the homework template. Anyway,

syncstarr said:
The moon orbits Earth in 27.3 days. suppose a spacecraft leaves the moon and follows the same orbit as the moon. if the spacecraft has a constant angular acceleration of 1.0 X 10^ -10 rad/s 62 what is its angular speed after 12h of flight? (Hint: At take off the spaceship has the same angular speed as the moon)

MY ANSWER:
given: angular acceleration =1.0X 10^-10 rad/s^2
t=12hours w final=?

equation: w final = w initial + angular accelerationt
=0+1.0X 10^-10(12)
=1.2 X 10^-9 rad/sec^2
Is this correct?? is my work and answer correct??

I can't figure out what you've done here. You didn't find the initial angular velocity, did you? Further on, convert days to seconds, and then calculate.

syncstarr said:
2. Consider a common analog clock. at midnight the hour and minute hands coincide. then the minute haand begins to rotate away from the hour hand. suppose you adjust the clock by pushing the hour hand clockwise with a constant acceleration. after 60.0 min, the hour hand has the same angular speed as the minute hand. calculate the hour hands angular acceleration.

my answer/work:
givn:
angular acceleration=?
w initial =12
w finial=60.0
t=1
equation:
w final= w initiaila+(angular acceleration )(t)
60=12+ angular acceleration (1)
60-12= angular acceleration
48 rad/s

are these the correct work and answers to these two problems? if you know either or both please let me know by leaving me a comment! THANK YOU VERY MUCH FOR TAKING THE TIME TO READ THIS! i just want to check parts of my homework problems that i am unsure about. so if you can help me please do. THANKs

It seems to me you are mixing up angular velocities with time.
 
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