PHY303k_-_Spring_2010_-_HW_13

PHY303k_-_Spring_2010_-_HW_13 - saldana (avs387) Homework...

Info iconThis preview shows pages 1–2. 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 DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: saldana (avs387) Homework 13 florin (58140) 1 This print-out should have 10 questions. Multiple-choice questions may continue on the next column or page find all choices before answering. 001 10.0 points The speed of a moving bullet can be deter- mined by allowing the bullet to pass through two rotating paper disks mounted a distance 98 cm apart on the same axle. From the angular displacement 19 . 5 of the two bul- let holes in the disks and the rotational speed 1223 rev / min of the disks, we can determine the speed of the bullet. 19 . 5 v 1223 rev / min 98 cm What is the speed of the bullet? Correct answer: 368 . 782 m / s. Explanation: Let : = 1223 rev / min , d = 98 cm , and = 19 . 5 . = t t = , so the speed of the bullet is v = d t = d = (98 cm) (1223 rev / min) 19 . 5 360 1 rev 1 m 100 cm 1 min 60 s = 368 . 782 m / s . keywords: 002 10.0 points A bug is on the rim of a 78 rev / min, 12 in . diameter record. The record moves from rest to its final angular speed in 2 . 93 s. Find the bugs centripetal acceleration 1 . 5 s after the bug starts from rest. (1 in = 2.54 cm). Correct answer: 2 . 66489 m / s 2 . Explanation: Let : w = 78 rev / min , t = 2 . 93 s , r = 6 in , and t = 1 . 5 s . = t , so = t = t t = 78 rev / min 2 . 93 s (1 . 5 s) 1 min 60 s = 4 . 18165 rad / s , and a r = v 2 t r = r 2 = (6 in)(4 . 18165 rad / s) 2 1 cm 2 . 54 in 1 m 100 cm = 2 . 66489 m / s 2 . 003 10.0 points A small wheel of radius 1 . 4 cm drives a large wheel of radius 13 . 9 cm by having their cir- cumferences pressed together....
View Full Document

Page1 / 5

PHY303k_-_Spring_2010_-_HW_13 - saldana (avs387) Homework...

This preview shows document pages 1 - 2. Sign up to view the full document.

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