This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Overton, Mays Homework 1 Due: Jan 24 2005, 4:00 am Inst: Turner 1 This printout should have 11 questions. Multiplechoice questions may continue on the next column or page find all choices before answering. The due time is Central time. 001 (part 1 of 1) 10 points A newly discovered giant planet has an aver age radius 16 times that of the Earth and a mass 364 times that of the Earth. Calculate the ratio of the new planets den sity to the Earths density. Correct answer: 0 . 0888672 . Explanation: Let : R n = 16 R E and m n = 364 m E . Density is the ratio of mass to volume, = m V . A spherical planet of average radius R has volume 4 3 R 3 and hence density = m 4 3 R 3 . For two planets of respective radii R 1 and R 2 and masses m 1 and m 2 we have 1 2 = m 1 4 3 R 3 1 m 2 4 3 R 3 2 = m 1 m 2 R 1 R 2 3 = 364 (16) 3 = . 0888672 . 002 (part 1 of 1) 10 points A sphere of metal has a radius of 5 . 5 cm and a density of 7 . 5 g / cm 3 . What is the mass of the sphere? Correct answer: 5226 . 82 g. Explanation: Let : r = 5 . 5 cm and = 7 . 5 g / cm 3 . Density is mass per unit volume, so = m V m = V = 4 3 r 3 = ( 7 . 5 g / cm 3 ) 4 3 (5 . 5 cm) 3 = 5226 . 82 g . 003 (part 1 of 1) 10 points A cylinder, 16 cm long and 2 cm in radius, is made of two different metals bonded endto end to make a single bar. The densities are 4 . 5 g / cm 3 and 6 . 4 g / cm 3 . 1 6 c m 2 cm What length of the lighter metal is needed if the total mass is 1076 g? Correct answer: 8 . 82876 cm....
View Full
Document
 Spring '08
 Turner
 Physics, Work

Click to edit the document details