Problem:

A bicycle wheel is mounted on a fixed, frictionless axle, with a light string wound around its rim. The wheel has moment of inertia I=kmr2, where m is its mass, r is its radius, and k is a dimensionless number between zero and one. The wheel is rotating counterclockwise with angular velocity (SYMBOL1), when at time t=0 someone starts pulling the string with a force of magnitude F.

Assume that the string does not slip on the wheel.

A. Suppose that after a certain time tL, the string has been pulled through a distance L. What is the final rotational speed of the wheel?

Express (SYMBOL1) in terms of L, r, F, k, m and (SYMBOL2)

B. What is the instantaneous power delivered to the wheel via the force F at time T=0?

Express the power in terms of the variables given in the problem introduction.

(PLEASE SEE ATTACHMENT FOR PROPER SYMBOLS AND DIAGRAM)

Pulling a String Adds Energy to a Wheel

.

Assume that the string does not slip on the wheel.

. What is the final rotational speed of the wheel?

.

?

Express the power in terms of the variables given in the problem

introduction.

Â [Â HYPERLINK "javascript:window.print();" Print Â ]Â

A bicycle wheel is mounted on a fixed, frictionless axle, with a light string wound around its rim. The wheel has moment of inertia I=kmr2, where m is its mass, r is its radius, and k is a dimensionless number between zero and one. The wheel is rotating counterclockwise with angular velocity (SYMBOL1), when at time t=0 someone starts pulling the string with a force of magnitude F.

Assume that the string does not slip on the wheel.

A. Suppose that after a certain time tL, the string has been pulled through a distance L. What is the final rotational speed of the wheel?

Express (SYMBOL1) in terms of L, r, F, k, m and (SYMBOL2)

B. What is the instantaneous power delivered to the wheel via the force F at time T=0?

Express the power in terms of the variables given in the problem introduction.

(PLEASE SEE ATTACHMENT FOR PROPER SYMBOLS AND DIAGRAM)

Pulling a String Adds Energy to a Wheel

.

Assume that the string does not slip on the wheel.

. What is the final rotational speed of the wheel?

.

?

Express the power in terms of the variables given in the problem

introduction.

Â [Â HYPERLINK "javascript:window.print();" Print Â ]Â

### Recently Asked Questions

- Chemists commonly use a rule of thumb that an increase of 10 °C in temperature doubles the rate of certain types of reactions . What must the activation

- A bead is moving with a speed of 20 m/s at position A on the track shown in the figure . This track is friction-free , and there is no appreciable air

- Suppose the economy 's saving schedule shifts from S 1 to S 2 as shown in the below diagram . We can say that its :