## Lesson 4: Velocity and Acceleration in Two Dimensions

## Overview:

A change in velocity occurs when there is a change in the velocity's magnitude or direction. Acceleration depends on the change in velocity, so acceleration in two dimensions also depends on a change in the velocity's magnitude, direction, or both.

Now that you are familiar with the component method for adding vectors, you can use this method to calculate two dimensional average velocity and average acceleration.

Now that you are familiar with the component method for adding vectors, you can use this method to calculate two dimensional average velocity and average acceleration.

## Curriculum Expectations:

**Specific Expectations:**

**B2.1**Use appropriate terminology related to dynamics, including, but not limited to: inertial and non-inertial frames of reference, components, centripetal, period, frequency, static friction, and kinetic friction.

**B2.2**Solve problems related to motion, including projectile and relative motion, by adding and subtracting two-dimensional vector quantities, using vector diagrams, vector components, and algebraic methods.

## Success Criteria:

- What two things are required for an object's velocity to change?
- What can cause acceleration?
- Describe how you can calculate the average velocity when there are several displacements, each with a different direction?
- Describe how to do vector subtraction of two vectors.
- What does it mean to multiply a vector by: (i) a number bigger than one and (ii) a number between 0<k<1?
- Describe how to find the average acceleration with vectors.

## Time Allocation: 3 hours

## Learning A

ctivities:**Read**pages 30 - 34 from Nelson 1.4

In the playlist below, video:

- Will show you how to subtract vectors graphically.
- Will show you how to subtract vectors numerically.

**Practice**questions 1 and 2 on page 32.

## Task:

**Solve**questions 3, 6, 8, 10 and 11 from Nelson 1.4 Review on page 35.

## Reflect:

You learned about different ways the motion of an object is measured and depicted and how various other parameters are calculated. Can you explain various physical phenomena where these concepts can be applied? Are there any exceptions to these concepts and theories in the real world?