In physics, every physical quantity is measured with respect to a unit. Time is measured in seconds, length is measured in meters, and mass is measured in kilograms. Knowing the units of physical quantities will help you solve problems in physics. Part A Gravity causes objects to be attracted to one another. This attraction keeps […]

## Converting between Different Units

Unit conversion problems can seem tedious and unnecessary at times. However, different systems of units are used in different parts of the world, so when dealing with international transactions, documents, software, etc., unit conversions are often necessary. Here is a simple example. The inhabitants of a small island begin exporting beautiful cloth made from a […]

## Converting Units: The Magic of 1

Learning Goal: To learn how to change units of physical quantities. Quantities with physical dimensions like length or time must be measured with respect to a unit, a standard for quantities with this dimension. For example, length can be measured in units of meters or feet, time in seconds or years, and velocity in meters […]

## Measurements in SI Units

Familiarity with SI units will aid your study of physics and all other sciences. Part A What is the approximate height of the average adult in centimeters? Part B Approximately what is the mass of the average adult in kilograms?

## Multiple Choice Question 1.22

A bird flies 3.0 km due west and then 1.2 km due north. Part A What is the magnitude of the bird’s displacement?

## Multiple Choice Question 1.23

A bird flies 2.8 km due west and then 2.1 km due north. Another bird flies 2.1 km due west and 2.8 km due north. Part A What is the angle between the net displacement vectors for the two birds?

## Problem 1.12

A dog trots from -11m to 2.0m in 12s. Part A What is its velocity? Express your answer using two significant figures.

## Problem 1.33

A kicker punts a football from the very center of the field to the sideline 45 yards downfield. Part A What is the magnitude of the net displacement of the ball? (A football field is 52 yards wide.) Note that the unit expression for yards is yd. Express your answer to two significant figures and […]

## Problem 1.34

Problem 1.34 is a motion problem similar to those you will learn to solve in Chapter 2. For now, simply interpret the problem by choosing the correct motion diagram showing the object’s position and its velocity vectors. Do not solve this problem or do any mathematics. Part A In a typical greyhound race, a dog […]

## Problem 1.38

Problem 1.38 is motion problem similar to those you will learn to solve in Chapter 2. For now, simply interpret the problem by drawing a motion diagram showing the object’s position and its velocity vectors. Do not solve this problem or do any mathematics. Part A The giant eland, an African antelope, is an exceptional […]