1. 10.1: An object in motion changes position. Review Questions (pg. 318)

2. What information do you need to describe an object’s location?
a reference point
Describe how your position changes as you jump over an object.
As a person jumps over an object, both his horizontal and vertical positions change.

3. Give an example of how the apparent motion of an object depends on the observer’s motion.
A person in an airplane will think of her or his seat as not moving, but an observer on the ground will think the seats are moving with the airplane.

4. The school is one block south of Jana’s home.
INFER Kyle walks 3 blocks south from his home to school, and Jana walks 2 blocks north from her home to Kyle’s home. How far and in what direction is the school from Jana’s home?
The school is one block south of Jana’s home. N
Kyle’s house W E
Jana’s house S
school

5. 5. Predict If you sit on a moving bus and toss a coin straight up into the air, where will it land?
back in your hand (or directly beneath where you threw it).
If you have a hard time picturing this, we can test it. One volunteer will sit in my chair while someone else pushes him/her across the room. The person in the chair will throw a coin straight up into the air and we will watch to see where it lands.

6. 6. Infer Jamal is in a car going north
6. Infer Jamal is in a car going north. He looks out his window and thinks that the northbound traffic is moving very slowly. Ellen is in a car going south. She thinks the northbound traffic is moving quickly. Explain why Jamal and Ellen have different ideas about the motion of the traffic.

7. Jamal and Ellen have different ideas because they are moving in different directions and have a different point of reference.
From Jamal’s point of view, traffic is going in the same direction as he is, and therefore seems to be moving slowly.
From Ellen’s point of view, traffic is moving in the opposite direction, and therefore seems to be moving quickly.

8. Ellen’s car
Jamal’s car
traffic