A person measures his or her heart rate by counting the number of beats in 30 s . If 40 1 beats are counted in 30.0 0.5 s , what is the heart rate and its uncertainty in beats per minute?
PHYS 101 LECTURE NOTES WEEK 1 Spencer Kociba Drexel University Lecture 1 (01/10/17) Dr. Brigita Urbanc bu25@drexel.edu Notes about the class in general: ● Lecture attendance counts (taken using Learning Catalytics: a Pearson add-on that should come with MasteringPhysics. It’s a polling system where before the lecture the professor will email/give the session code for the day) ● All information for the course will be in BBLearn (but the labs have a separate website they may use) ● Course ID for MasteringPhysics: urbanc 67863 (section C) ● Prelectures are due Tuesday by 9am (no matter what section you are) Chapter 1: Units, Physical Quantities and Vectors ● Basic Physical Quantities ○ Length, time, mass (meters, seconds and kilograms are most commonly used) −6 ○ μm = micron/micrometer = 10 m ○ nm = nanometer = 10 ○ 1in= 2.54cm ○ Use conversion factors (which are equal to 1) to change units ● Scalar quantities ○ Single numbers (has a unit) ○ Note: speed is a scalar quantity because it is the magnitude of a vector but not the direction. ● Vector quantities ○ Values that describe something with both magnitude and direction (positive values) ● Vectors ○ ○ Equal if they have the same magnitude and direction
