The typical 19 wheel on a car has a moment of inertia of 3.1 kg m2....

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The typical 19" wheel on a car has a moment of inertia of 3.1 kg m2. Defining counterclockwise motion as positive, answer the following questions; each of these is its own separate calculation, the later parts do not depend on the earlier parts. Problem 1. The wheel is spinning when we apply a torque to it over a period of 4 s. If its initial angular velocity is 6 rad/s counterclockwise and the torque applied is 15 N m, what is the wheel's final angular momentum? kg m2/s Problem 2. A torque of 4 N m is applied to accelerate a wheel from rest. You measure its final angular velocity to be 12 rad/s. How long must the torque have been applied to the wheel? S Problem 3. Over 12 s, a constant torque is applied to the wheel. Initially, the wheel was moving 6 rad/s clockwise, but after the torque is applied, it is moving 6 rad/s counterclockwise. What torque was applied to the wheel? Nm + Show My Work (Optional) ? 8. [-/18 Points] DETAILS Weird astrophysical objects MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER When a star between ~9-25 solar masses reaches the end of its life, fusion in the core halts and the core can no longer withstand gravitational pressure. Gravity causes the ~2.5 solar mass core to collapse, triggering a supernova. In this process, the roughly Earth-sized core (6345 km) will collapse down into a neutron star the size of a small city, about 10.3 km. If the star had a rotation period of 179 s before collapse and a negligible amount of mass was lost from this core in the supernova, what is the neutron star's new rotation period? S How many times per second does the neutron star rotate? rev/s *N.b.: neutron stars don't emit light themselves (weird that they're called 'stars' at all), so they were first discovered via radio emission as their magnetic fields interact with nearby particles. The first pulsar discovered was nicknamed LGM-1 by researchers, for Little Green Men. The typical 19" wheel on a car has a moment of inertia of 3.1 kg m2. Defining counterclockwise motion as positive, answer the following questions; each of these is its own separate calculation, the later parts do not depend on the earlier parts. Problem 1. The wheel is spinning when we apply a torque to it over a period of 4 s. If its initial angular velocity is 6 rad/s counterclockwise and the torque applied is 15 N m, what is the wheel's final angular momentum? kg m2/s Problem 2. A torque of 4 N m is applied to accelerate a wheel from rest. You measure its final angular velocity to be 12 rad/s. How long must the torque have been applied to the wheel? S Problem 3. Over 12 s, a constant torque is applied to the wheel. Initially, the wheel was moving 6 rad/s clockwise, but after the torque is applied, it is moving 6 rad/s counterclockwise. What torque was applied to the wheel? Nm + Show My Work (Optional) ? 8. [-/18 Points] DETAILS Weird astrophysical objects MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER When a star between ~9-25 solar masses reaches the end of its life, fusion in the core halts and the core can no longer withstand gravitational pressure. Gravity causes the ~2.5 solar mass core to collapse, triggering a supernova. In this process, the roughly Earth-sized core (6345 km) will collapse down into a neutron star the size of a small city, about 10.3 km. If the star had a rotation period of 179 s before collapse and a negligible amount of mass was lost from this core in the supernova, what is the neutron star's new rotation period? S How many times per second does the neutron star rotate? rev/s *N.b.: neutron stars don't emit light themselves (weird that they're called 'stars' at all), so they were first discovered via radio emission as their magnetic fields interact with nearby particles. The first pulsar discovered was nicknamed LGM-1 by researchers, for Little Green Men.

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