Forces Mr Welhouse Debriefing the Lab Group Acceleration

Forces Mr. Welhouse

Debriefing the Lab Group Acceleration Mass

Relationships of variables

What units go with each concept? � Mass: � Acceleration: � Force:

Graphs

Using what we learned � If mass goes up and acceleration stays the same, what happens to force? � A. Stays the same � B. Goes up � C. Goes down

Using what we learned � If mass stays the same but we use more force to pull the object, what happens to the acceleration? � A. Acceleration stays the same � B. Acceleration decreases � C. Acceleration increases

Using what we learned � How much mass can we pull at a constant acceleration of 4 m/s/s if we use a force of 20 Newtons? Known Values Equation Work Answer and Units

� Suppose we can produce a constant force of 180 Newtons. Can we stop the boulder in time to avert disaster? �A boulder has a mass of 50 kg. It is moving toward the cliff at 4 m/s. We will push against the motion of the boulder. If we need the boulder to stop in under 6 seconds, is our force strong enough? Known Values Equation Work Answer and Units

Fill in the graphs. P o s i t i o n V e l o c i t y Time

Fill in the graphs

Fill in the graphs P o s it i o n Time A c c e l. V e l o c i t y Time F o r c e Time

Fill in the graphs using what is given. P o s it i o n V e l o c i t y Time A c c e l. Time F o r c e Time

Forces � Push/pull that changes the velocity of mass � What are some examples of forces?

Newton’s Laws � I. Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it. (definitions from University of Tennessee Astronomy 161 website) � Please put the law in your own words.

Newton’s Laws � II. The relationship between an object's mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors (as indicated by their symbols being displayed in slant bold font); in this law the direction of the force vector is the same as the direction of the acceleration vector. � What is important from this law?

Newton’s Laws � III. For every action there is an equal and opposite reaction. � Put this law in your own words.

Examples

Types of Forces � Contact � Examples: � Field � Examples:

Force Activity � Go to : http: //www. youtube. com/watch? v=P 6 vc. WP 3 s. Glc � Pick at least three instances in the video and record the times. � How are the Newton’s Laws illustrated in each example? � What types of forces are present at each point?