Name:______Date:______Period:_____

Chapter 19 Honors Study Guide

  1. What is a reference point?

The starting point you use to describe the motion or the position of an object

  1. What is acceleration? Negative acceleration?

The measure of how quickly the velocity of an object changes; when an object’s initial velocity is greater than its final velocity

  1. Define speed?

The distance an object moves divided by the time it took to move that distance

  1. What is the difference between displacement and distance?

Displacement is the distance between your initial, or starting, position and your final position. The distance is the total length of the path you travel. Displacement will never change but your distance can.

  1. What is velocity? And how is it usually represented?

The speed and direction of an object’s motion; m/s + a direction

  1. What is motion?

Is the process of changing position

  1. What is needed to describe velocity?

Speed and direction

  1. On a displacement-time graph, how is an object that is not moving represented?

A horizontal line

  1. On a speed-time graph, how is an object that is slowing down represented?

A line slanting down

  1. What is found on the x and y axis on a speed time graph?

X axis-time, y-axis-speed

  1. What is a contact force? Give an example.

A push or a pull applied by one object to another object that is touching it. Examples: Holding a pencil, kneading dough, elastic forces

  1. What is a non-contact force? Give an example.

A force that pushes or pulls an object without touching it. Examples: static electricity, magnetic forces, gravity

  1. What is friction?

A contact force that resists the sliding motion between two objects that are touching. The forceof friction acts in the opposite direction of the motion.

  1. What is gravity?

A noncontact attractive force that exists between all objects that have mass

  1. What is the difference between balanced and unbalanced forces?

Balanced forces have a net force of 0 N and unbalanced forces have a net force that is not 0.

  1. The force of gravity depends on what two things?

The masses of the objects and the distances between them

  1. If team A is pulling on a rope at 150 N to the left, and team B is pulling on a rope at 120 N to the right, what is the net force on the rope?

30 N to the left

  1. What is a net force?

The sum of all the forces acting on anobject

  1. What is a force?

A push or a pull

  1. What are the proper units for:

-acceleration? ___m/s2______

-velocity? ___m/s + direction

- speed? ______m/s______

Essays

  1. A pitcher releases a fastball that moves toward home plate. Other than the force exerted by the pitcher, what are two forces that act on the ball as it travels between the pitcher and home plate? How does each of these forces change the ball’s motion? Classify the forces acting on the ball as balanced or unbalanced.

Two forces that act on the ball as itmoves through the air are gravity and friction. Gravity causes the ball to move downward toward Earth. Friction causes the ball’s motion to get slower the farther it moves through the air. Because the ball’s velocity is changing as it moves, it can be determined that the forces acting on the ball are unbalanced.

2.

Explain the polar bear’s motion at parts A, B, C, and D on the graph.

In part A the polar bear is at rest. From hours 3-7 (Part B), the polar bear is speeding up. In part C (hours 7-11) the polar bear is traveling at a constant speed. In part D (hours 11-15) the line slanting down is showing that the polar bear is slowing down.