2 Masses on a Pulley - Torque Demonstration

The video tutorial explains a physics problem involving a pulley system with two masses and a frictionless pulley. It covers the calculation of angular acceleration and forces of tension, using free body diagrams and equations. The tutorial also addresses common mistakes and provides a detailed solution to the problem, emphasizing the importance of considering rotational inertia and net torque.

What is the rotational inertia of the pulley described in the problem?

• 0.0385 kg·m²

• 0.200 kg·m²

• 0.0137 kg·m²

• 0.100 kg·m²

Why can't the tension forces on either side of the pulley be the same?

• Because the pulley is frictionless

• Because the pulley has mass and rotational inertia

• Because the string is elastic

• Because the masses are equal

What is the direction defined as positive for the torque in this problem?

• Downward

• Clockwise

• Upward

• Counterclockwise

How is the angular acceleration of the pulley calculated?

• Using the sum of torques

• Using the mass of the pulley

• Using the initial velocity

• Using the sum of forces

What is the predicted angular acceleration of the pulley?

• 2.43 radians/s²

• 4.00 radians/s²

• 3.21 radians/s²

• 2.67 radians/s²

What is the force of tension in the string connected to mass 1?

• 3.21 N

• 0.991 N

• 1.94 N

• 2.67 N

What is the force of tension in the string connected to mass 2?

• 2.67 N

• 0.991 N

• 3.21 N

• 1.94 N

Why is it incorrect to sum the torques on the whole system at once?

• Because the masses do not have rotational inertia

• Because the pulley is not rotating

• Because the pulley has no friction

• Because the masses have rotational inertia

What happens if the pulley has negligible mass and rotational inertia?

• The forces of tension would be different

• The forces of tension would be the same

• The string would break

• The pulley would not rotate

What does negligible friction in the context of this problem mean?

• The string has no tension

• The pulley does not rotate

• The axle of the pulley has negligible friction

• The string slides on the pulley