Question
Here are the 5 questions,
The two objects at right have the same mass (and the drawings are at the same scale). Which has the larger moment of inertia relative to the axes shown? 1 2 both the same both have zero moment of inertia none of these The two rotating spheres shown in the figure have different masses and moments of inertia. They move toward each other until the touch briefly. Since there is friction, their angular velocities change as a result of the contact Assuming the spheres interact only among themselves, the total angular momentum of the system after they separate is larger than before they came into contact is the same than before they came into contact is smaller than before they came into contact may be smaller or larger than before they came into contact. depending on how fast they are spinning is zero The system at right is spinning as shown It consists of two thin disks connected a rigid rod of negligible mass. If the rod suddenly contracts to half its initial length the angular velocity decreases as a result of conservation of angular momentum the angular velocity increases as a result of conservation of angular momentum the angular momentum decreases as a result of conservation of energy the angular momentum decreases as a result of conservation of energy the rotational kinetic energy stays the same The string of the yo-yo shown in the figure is tied to ceiling. The yo-yo is then allowed to fail. If the moment of inertia I relative to the center of mass of the yo-yo is different from zero, the downward linear acceleration is equal to g larger than g smaller than g depends on the initial velocity given to the yo-yo depends on the initial angular momentum of the yo-yo In static equilibrium the linear acceleration is zero, but not the angular acceleration both linear and angular acceleration are zero the angular acceleration is zero, but not the linear acceleration the total torque is zero only relative to the center of mass the total force is zero only if the torque is computed relative to the center of mass
Explanation / Answer
1.
As the 1 figure has more mass Distance from the axes . SO more MOI
So
(A) 1
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2.
As there is no External Force so Total Angular Momemtum remains Conseved
So B option
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3.
As Distance between the center and Discs Decreases
So MMoment of Inewrtia Decreases
As Ansgular Momentum is Oncserd
Therfore
Angular Velocity Increases
B option
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4.As yoyo has moment of Inertia
As we know in General
Acceleration = g/(1 + I/MR^2)
Here I for Disc yoyo = 0.5*M*R^2
Therefore
Acceleration = g/(1 + 1/2)
= (2/3)g < g
Therfore
C option is Correct
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5.
For Static Equilibrium both Linear accceleration and angulalr acceleraton must be Zero
B option
