hw 10 erskine - bahr(kcb532 – Homework#10 – Erskine...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: bahr (kcb532) – Homework #10 – Erskine – (58200) 1 This print-out should have 24 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. 001 10.0 points A massless rod of length L has a mass m fastened at one end and a mass 2 m fastened at the other end. What is the ratio of the moment of inertia about an axis through the mass m to the moment of inertia through the center of the rod? 1. 3 8 2. 8 3 3. 3 4 4. 1 2 5. 2 3 6. 3 2 7. 4 3 8. 2 002 10.0 points A spool (similar to a yo-yo) is pulled in three ways, as shown below. There is sufficient friction for rotation. a b c In what direction will each spool move (in the order spool a, spool b, spool c)? 1. right; right; right 2. right; left; right 3. left; right; right 4. None of these is correct. 5. right; right; left 6. right; left; left 003 10.0 points A circular-shaped object of mass 15 kg has an inner radius of 13 cm and an outer radius of 21 cm. Three forces (acting perpendicular to the axis of rotation) of magnitudes 11 N, 24 N, and 15 N act on the object, as shown. The force of magnitude 24 N acts 29 ◦ below the horizontal. 11 N 15 N 24 N 29 ◦ ω Find the magnitude of the net torque on the wheel about the axle through the center of the object. Answer in units of N · m. 004 10.0 points Chimneys which fall over often break apart in mid-fall because the mortar between the bricks cannot withstand much tension force. As the chimney falls, this tension supplies the centripetal forces on the topmost segments that they need to keep them traveling in an arc. For simplicity, let us model the chimney as a uniform rod of length ℓ pivoted at the lower end. The rod starts at rest in a vertical position (with the pivot at the bottom) and falls over under the influence of gravity. What fraction of the length of the rod has a tangential acceleration greater than g sin θ where θ is the angle the chimney makes with a vertical line? 1. 2 3 bahr (kcb532) – Homework #10 – Erskine – (58200) 2 2. 3 5 3. 1 3 4. 2 5 5. 3 7 005 10.0 points A uniform horizontal rod of mass 2 . 3 kg and length 2 . 4 m is free to pivot about one end as shown. The moment of inertia of the rod about an axis perpendicular to the rod and through the center of mass is given by I = mℓ 2 12 . 2 . 4 m F 9 8 ◦ pivot 2 . 3 kg If a 3 N force at an angle of 98 ◦ to the hor- izontal acts on the rod as shown, what is the magnitude of the resulting angular accelera- tion about the pivot point? The acceleration of gravity is 9 . 8 m / s 2 . Answer in units of rad / s 2 ....
View Full Document

{[ snackBarMessage ]}

Page1 / 6

hw 10 erskine - bahr(kcb532 – Homework#10 – Erskine...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online