# A group of students must conduct an experiment to determine how the location of an applied force on a classroom door affects the rotational motion of the door. The rotational inertia of the door about its hinges is known. The initial angular velocity of the door is zero. The students must determine how to test the relationship between a torque exerted on the door and the change in the angular velocity of the door. All frictional forces are considered to be negligible. How should the experiment be conducted to test the relationship between the torque exerted on the door and the change in the door's angular velocity in a way that minimizes experimental uncertainty?

A group of students must conduct an experiment to determine how the location of an applied force on a classroom door affects the rotational motion of the door. The rotational inertia of the door about its hinges is known. The initial angular velocity of the door is zero.

The students must determine how to test the relationship between a torque exerted on the door and the change in the angular velocity of the door. All frictional forces are considered to be negligible.

How should the experiment be conducted to test the relationship between the torque exerted on the door and the change in the door’s angular velocity in a way that minimizes experimental uncertainty?

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1. The students should perform several trials, applying the same force at different horizontal distances from the hinges.

2. To conduct an experiment that tests the relationship between the torque exerted on the door and the change in the door’s angular velocity while minimizing experimental uncertainty, the students should follow these steps:

1. Ensure that the door is initially at rest (zero angular velocity) before applying any force.
2. Apply a known force perpendicular to the door at different positions (distances from the hinges) and measure the corresponding change in angular velocity of the door. This can be done by marking different points on the door and using a timer or motion sensor to measure the angular velocity after applying the force.
3. Calculate the torque for each applied force using the formula: torque = force × perpendicular distance from the hinge.
4. Plot the data points with torque on the x-axis and the change in angular velocity on the y-axis.
5. Repeat the experiment multiple times for each force position to obtain an average value and minimize the effect of random errors.
6. Ensure that the force is applied as a sharp impulse and released immediately to avoid the influence of friction or air resistance during the motion of the door.
7. Use a force sensor or a known weight to apply the force consistently and accurately measure its magnitude.
8. Perform the experiment in a controlled environment with minimal air currents or external disturbances that could affect the motion of the door.
9. Use a level surface and ensure that the door hinges are properly aligned and lubricated to minimize the effect of non-negligible frictional forces.
10. Use a high-precision timer or motion sensor to accurately measure the angular velocity changes.