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URGENT: Shown below is a small particle of mass 23 g that is moving at a speed of 10 m/s when it collides with and sticks to the edge of a uniform solid cylinder. The cylinder is free to rotate about the axis through its center and perpendicular to the page. The cylinder has a mass of 0.8 kg and a radius of 12 cm and is initially at rest.

(a) What is the angular velocity (in rad/s) of the system after the collision? (Indicate the direction with the sign of your answer.)

(b) How much kinetic energy (in J) is lost in the collision?

URGENT: Shown below is a small particle of mass 23 g that is moving at a speed of-example-1

1 Answer

7 votes

a. The angular velocity of the system after the collision is 0 rad/s.

b. The1.15 J of kinetic energy is lost in the collision.

(a) Angular Velocity after Collision

The angular velocity of the system after the collision can be calculated using the principle of conservation of angular momentum. The initial angular momentum of the system is zero, since the cylinder is initially at rest. The final angular momentum of the system is equal to the product of the moment of inertia of the system and its angular velocity.

The moment of inertia of the cylinder about its center can be calculated using the formula:

I = (1/2)MR²

Where:

I is the moment of inertia (kg m²)

M is the mass of the cylinder (kg)

R is the radius of the cylinder (m)

Plugging in the given values, we get:

I = (1/2)(0.8 kg)(0.12 m)² = 0.00576 kg m²

The final angular momentum of the system can be calculated using the formula:

L = Iω

Where:

L is the angular momentum (kg m²/s)

I is the moment of inertia (kg m²)

ω is the angular velocity (rad/s)

Setting the initial angular momentum equal to the final angular momentum, we get:

0 = Iω

Solving for ω, we get:

ω = 0 rad/s

Therefore, the angular velocity of the system after the collision is 0 rad/s.

(b) Kinetic Energy Lost in Collision

The kinetic energy lost in the collision is equal to the difference between the initial kinetic energy of the particle and the final kinetic energy of the system. The initial kinetic energy of the particle can be calculated using the formula:

KE = (1/2)mv²

Where:

KE is the kinetic energy (J)

m is the mass of the particle (kg)

v is the velocity of the particle (m/s)

Plugging in the given values, we get:

KE = (1/2)(0.023 kg)(10 m/s)² = 1.15 J

The final kinetic energy of the system is zero, since the system is at rest after the collision. Therefore, the kinetic energy lost in the collision is equal to the initial kinetic energy of the particle:

KE_lost = 1.15 J

Therefore, 1.15 J of kinetic energy is lost in the collision.

User Niran Manandhar
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