Unit 7, Section 1 - Acceleration

Unit 7, Section 1 - Motion

Day 3 - Acceleration

Multiple Choice

Review Question 1: A car travels 450 miles in 10.5 hours. The car's average speed is:

• 0.023 miles per hour

• 450 miles per hour

• 42.9 miles per hour

• 4,725 miles per hour

Multiple Choice

Review Question 2: A plane flies at a speed of 375 miles per hour for 5.4 hours. The distance that the plane traveled was:

• 2,025 miles

• 0.014 miles

• 375 miles

• 69.4 miles

• We can now calculate the velocity of an object (a car, for example)

• But what if the object speeds up, or slows down?

  • In other words, can we determine how its velocity is changing?

  • Yep!  It's called acceleration

Acceleration - A change in velocity divided by the time it took that change to occur

Acceleration

Formula For Acceleration

Example Problem - Together

It takes 5 seconds for a drone to speed up from 5 meters per second to 15 meters per second.  What is the drone’s acceleration?

Open Ended

On-Your-Own Problem: It takes 2 seconds for a cheetah to speed up from 4.5 meters per second to 27 meters per second.  What is the cheetah’s acceleration?

An object slows down if it has negative acceleration.

Negative Acceleration

An object speeds up if it has positive acceleration.

Positive Acceleration

Positive and Negative Acceleration

Open Ended

If an object is "at rest", what is its speed?

Open Ended

An object at rest speeds up to 50 meters per second in 2.5 seconds. What is the object's acceleration?