If the force pairs act on objects so that the net forces acting on one object is not being balanced by any other force, then the force on that object is considered unbalanced. Unbalanced forces cause a change in motion (acceleration). Consider an avalanche. Before the avalanche, the force of gravity on the snow is equal to the force of friction between snowflakes (and any other force acting in opposition to gravity.)
The forces are balanced, so the snow is motionless. If some event, such as melting, reduces the frictional force so that it is less than the gravitational force, the net force will become unbalanced, and the snow will accelerate down the slope.
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Question 3
3.
Unbalanced forces cause a change in ___________.
Other Answer Choices:
yay
mass
motion
weight
height
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Question 4
4.
Before an avalanche, which two forces are balanced (equal)?
<Select all that apply>
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Question 5
5.
When the snow is motionless the forces applied to the snow are ____________________ . When the snow moves like in an avalanche, the forces applied to the snow are ______________________ .
Other Answer Choices:
balanced forces
unbalanced forces
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Question 6
6.
In an avalanche, what happens to the forces?
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Question 7
7.
Paragraph two explains how the forces of friction and gravity are in balance for snow that is not moving. Explain how an avalanche is created using paragraph 2 as a reference (1 point). Make sure to use the word unbalanced force in your answer (1 point).
Word Bank:
unbalanced force
balanced force
melting
friction
gravity
Sentence Starter: An avalanche is created as...
The same unbalanced forces result when a coffee cup falls to the floor. Before, the coffee cup pushes on the hand, which pushes back on the coffee cup. Next, the cup is dropped from the hand. With no contact force supporting the cup, gravity accelerates the cup downward. If an object is accelerating (speeding up, slowing down or changing directions), then we know the forces acting on that object must be unbalanced.
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Question 9
9.
Explain what would happen if the contact force of the hand supporting the brush was removed.
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Question 10
10.
What are the signs of acceleration and unbalanced forces being present.
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Question 11
11.
Where does gravity generally accelerate objects?
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Question 12
12.
Drag and drop the images/gifs to their appropriate categories.
The forces on the objects are unbalanced.
The forces on the objects are balanced.
However, not all pairs of forces result in an acceleration. If all the forces acting on a particular object are balanced so that the net force is zero, the object will not accelerate (Newton’s first law). The object will continue its current state of motion. If the object is at rest, it will stay at rest. Such was the case with the rock sitting on the ground. The net force is balanced, so the rock will remain at rest.
If the object is in motion and all forces on it are balanced, the object will continue to move at the same speed in the same direction. Such as with a plane moving north at 250 m/s. If all the forces acting on the plane are balanced, it will continue north at 250 m/s. The plane cannot slow down, speed up, or change directions without an unbalanced force to make it accelerate.
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Question 14
14.
According to the text, if all the forces acting on an object are balanced (or equal) than an object will not accelerate. Which objecy is an example of this?
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Question 15
15.
If an object moves at the same speed in the same direction then...
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Question 16
16.
An object is moving at the same speed in the same direction = __________________________________________
An object is increasing in speed, decreasing speed or changing direction = ____________________________________________
Other Answer Choices:
The forces are balanced on the object
The forces are unbalanced on the object
Required
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6
Question 17
17.
Complete an inforgraphic displaying balanced and unbalanced forces.
Must have:
* Definition of unbalanced and balanced forces (you can use the text or look up simple definitions)
* Draw images and provide an explanation of what is going on in your examples.
How can rockets accelerate? Rockets move forward by expelling gas backward at high velocity. This means the rocket exerts a large backward force on the gas in the rocket combustion chamber, and the gas, therefore, exerts a large reaction force forward on the rocket. This reaction force is called thrust. It is a common misconception that rockets propel themselves by pushing on the ground or on the air behind them. They actually work better in a vacuum, in which they can more readily expel the exhaust gases.
Required
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Required
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Question 19
19.
Explain the common misconception about how rockets are launched in the air.