a. What is the formula used to calculate the acceleration of an object moving in a straight line? b. A cyclist's speed changes from $0 \mathrm{~m} / \mathrm{s}$ to $15 \mathrm{~m} / \mathrm{s}$ in 10 seconds. What is the cyclist's average acceleration?

Convert 119 cm to meters .

A family takes a car trip. They travel for an hour at $80 \mathrm{~km} / \mathrm{h}$ and then for 2 hours at $40 \mathrm{~km} / \mathrm{h}$. Find their average speed during the trip.

Two drivers make a $100-\mathrm{km}$ trip. Driver 1 completes the trip in 2 hours. Driver 2 takes 3 hours but stops for an hour halfway. Which driver had a greater average speed? Explain.

How can you tell if an object is moving when its motion is too slow to see?

The graph below shows the motion of a remote-control car. During which segment is the car moving the fastest? The slowest? How do you know?

An insect lands on a compact disc that is put into a player. If the insect spins with the disc, is the insect accelerating? Why or why not?

Which has a greater speed, a heron that travels $600 \mathrm{~m}$ in 60 seconds or a duck that travels $60 \mathrm{~m}$ in 5 seconds? Explain.

Both speed and acceleration include the direction of an object's motion.

A change in position with respect to a reference point is a. acceleration. b. velocity. c. direction. d. motion.

a. What are the three ways that an object can accelerate? b. Describe how a baseball player accelerates as he runs around the bases after hitting a home run. c. An ice skater glides around a rink at a constant speed of $2 \mathrm{~m} / \mathrm{s}$. Is the skater accelerating? Explain your answer.

a. What is speed? b. What do you know about the motion of an object that has an average speed of $1 \mathrm{~m} / \mathrm{s}$ ? c. What is the difference between speed and velocity?

a. Reviewing How do you know if an object is moving? b. Explaining Why is it important to know if your reference point is moving? c. Applying Concepts Suppose you are riding in a car. Describe your motion relative to the car, the road, and the sun.

a. What is speed? b. What do you know about the motion of an object that has an average speed of $1 \mathrm{~m} / \mathrm{s}$ ? c. What is the difference between speed and velocity?