What mass of a material with density r is required to make a hollow spherical shell having inner radius r1 and outer radius r2?

PHYSICS 1 – 1100 LECTURE 1 Measurements Physics is both quantitative and predictive Quantitative – We find measurements that determine physical variables Predictive – If we can predict the behavior of a physical system then we understand the system. Mathematical measurements Length – meter (m) Time – second (s) Mass – kilogram (kg) Converting Factors 1 mile = 1.609 km 1km = 0.6214 mi Example : 100 km = mi Use converting factor of 0.6214 because the km is the known number 100km x 0.6214mi/km = 62.14mi DEVIATION Deviation is defined as the difference between the average value and a data point. Each data point has its own deviation *Random variation is caused by unpredictable fluctuations due