Middle School Physical Science : Interpret force diagrams and sums of forces
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Example Questions
Example Question #1 : Interpret Force Diagrams And Sums Of Forces
Are the forces in this image balanced or unbalanced, and how is the object moving?
balanced and the object is moving right with a force of 50 Newtons
unbalanced and the object is moving left with a force of 50 Newtons
balanced and the object is moving left with a force of 50 Newtons
unbalanced and the object is moving right with a force of 50 Newtons
unbalanced and the object is moving left with a force of 50 Newtons
The answer is "unbalanced, the object is moving left with a force of 50 Newtons." The object is moving because the forces are unbalanced, and the net force is 50 Newtons to the left because the magnitude of that force is 50 Newtons stronger than the one going right.
When we make diagrams or drawings of forces, we use vectors. A vector is an arrow that represents the magnitude and the direction of a force. The magnitude is how strong the force is, usually in Newtons, and the direction can be expressed in north, south, east, west, left, right, up, or down.
In order to evaluate the sum of forces in a free body diagram you have to add the vectors of forces both in the horizontal and in the vertical direction. The sum of forces in all directions is called the “net force.” When forces are going in opposite directions, they should be subtracted or the value of one of the forces should be given a negative to account for the direction.
Example Question #1 : Interpret Force Diagrams And Sums Of Forces
What is the net force acting on this object?
500 N left, 200 N down
500 N left
900 N left
100 N
500 N left
The answer is "500 N left" because the upwards and downwards forces are balanced, and the leftward force is 500N.
When we make diagrams or drawings of forces, we use vectors. A vector is an arrow that represents the magnitude and the direction of a force. The magnitude is how strong the force is, usually in Newtons, and the direction can be expressed in north, south, east, west, left, right, up, or down.
In order to evaluate the sum of forces in a free body diagram you have to add the vectors of forces both in the horizontal and in the vertical direction. The sum of forces in all directions is called the “net force.” When forces are going in opposite directions, they should be subtracted or the value of one of the forces should be given a negative to account for the direction.
Example Question #2 : Interpret Force Diagrams And Sums Of Forces
What is the net force acting on this object?
3,710 N to the right
1,002 N to the right
3,710 N to the left
the net force is 0 N
1,002 N to the right
The answer is "1,002 N to the right" because the up and down forces are balanced, and the force acting towards the left is 1,0002 N stronger than the force acting to the right
Example Question #3 : Interpret Force Diagrams And Sums Of Forces
A soccer ball is kicked on the ground with 100 Newtons of force to the right. The ball never leaves the ground. What is the net force acting in the upwards and downwards direction?
The net force in the upwards and downwards direction is 50 Newtons.
The net force in the upwards and downwards direction is 100 Newtons.
The net force in the upwards and downwards direction is 25 Newtons.
The net force in the upwards and downwards direction is zero.
The net force in the upwards and downwards direction is zero.
The answer is "The net force in the upwards and downwards direction is zero."
When we make diagrams or drawings of forces, we use vectors. A vector is an arrow that represents the magnitude and the direction of a force. The magnitude is how strong the force is, usually in Newtons, and the direction can be expressed in north, south, east, west, left, right, up, or down.
In order to evaluate the sum of forces in a free body diagram you have to add the vectors of forces both in the horizontal and in the vertical direction. The sum of forces in all directions is called the “net force.” When forces are going in opposite directions, they should be subtracted or the value of one of the forces should be given a negative to account for the direction.
Example Question #4 : Interpret Force Diagrams And Sums Of Forces
What is the net force acting on this object?
1,400 Newtons
0 Newtons
400 Newtons
1000 Newtons
0 Newtons
The answer is "0 Newtons" because all the forces are balanced.
When we make diagrams or drawings of forces, we use vectors. A vector is an arrow that represents the magnitude and the direction of a force. The magnitude is how strong the force is, usually in Newtons, and the direction can be expressed in north, south, east, west, left, right, up, or down.
In order to evaluate the sum of forces in a free body diagram you have to add the vectors of forces both in the horizontal and in the vertical direction. The sum of forces in all directions is called the “net force.” When forces are going in opposite directions, they should be subtracted or the value of one of the forces should be given a negative to account for the direction.
Example Question #5 : Interpret Force Diagrams And Sums Of Forces
A box is falling from the sky and moving straight down with a force of 18,000 Newtons. What is the net force acting on the object?
9,000 Newtons right and 9,000 Newtons downward
9,800 Newtons downward and the rest in the other directions because acceleration due to gravity is 9.8
The net force is 0 because the box is falling and the forces are balanced
18,000 Newtons downward
18,000 Newtons downward
The answer is 18,000 Newtons because there is no normal force acting on the object in the upward direction if there is no surface below it.
When we make diagrams or drawings of forces, we use vectors. A vector is an arrow that represents the magnitude and the direction of a force. The magnitude is how strong the force is, usually in Newtons, and the direction can be expressed in north, south, east, west, left, right, up, or down.
In order to evaluate the sum of forces in a free body diagram you have to add the vectors of forces both in the horizontal and in the vertical direction. The sum of forces in all directions is called the “net force.” When forces are going in opposite directions, they should be subtracted or the value of one of the forces should be given a negative to account for the direction.
Example Question #5 : Interpret Force Diagrams And Sums Of Forces
True or false: A book sitting still on a table has no forces acting on it.
False
True
False
The answer is false. The book has forces acting on it but the net force is 0.
When we make diagrams or drawings of forces, we use vectors. A vector is an arrow that represents the magnitude and the direction of a force. The magnitude is how strong the force is, usually in Newtons, and the direction can be expressed in north, south, east, west, left, right, up, or down.
In order to evaluate the sum of forces in a free body diagram you have to add the vectors of forces both in the horizontal and in the vertical direction. The sum of forces in all directions is called the “net force.” When forces are going in opposite directions, they should be subtracted or the value of one of the forces should be given a negative to account for the direction.
Example Question #6 : Interpret Force Diagrams And Sums Of Forces
Two people are pushing on an object. One person pushes the object 20 Newtons to the right. The other person pushes the object 50 Newtons to the left. What is the net force on the object?
80 newtons
0 newtons
30 newtons to the left
50 newtons to the left
30 newtons to the left
The answer is 30 Newtons to the left.
When we make diagrams or drawings of forces, we use vectors. A vector is an arrow that represents the magnitude and the direction of a force. The magnitude is how strong the force is, usually in Newtons, and the direction can be expressed in north, south, east, west, left, right, up, or down.
In order to evaluate the sum of forces in a free body diagram you have to add the vectors of forces both in the horizontal and in the vertical direction. The sum of forces in all directions is called the “net force.” When forces are going in opposite directions, they should be subtracted or the value of one of the forces should be given a negative to account for the direction.
Example Question #2 : Interpret Force Diagrams And Sums Of Forces
The image above shows an object being pushed with a force, and the sum of forces in both directions. Why are some of the forces in this diagram negative?
Some of the forces are negative because they're "pulls" not "pushes".
Some of the forces are negative because they're going different directions.
None of these
Some of the forces are negative because they're "pushes" not "pulls".
Some of the forces are negative because they're going different directions.
The answer is "Some of the forces are negative because they're going different directions."
When we make diagrams or drawings of forces, we use vectors. A vector is an arrow that represents the magnitude and the direction of a force. The magnitude is how strong the force is, usually in Newtons, and the direction can be expressed in north, south, east, west, left, right, up, or down.
In order to evaluate the sum of forces in a free body diagram you have to add the vectors of forces both in the horizontal and in the vertical direction. The sum of forces in all directions is called the “net force.” When forces are going in opposite directions, they should be subtracted or the value of one of the forces should be given a negative to account for the direction.
Example Question #7 : Interpret Force Diagrams And Sums Of Forces
Describe the motion of this cylinder.
It is moving to the right and down with a force of 500 Newtons.
It is not moving with a force of 500 Newtons.
It is not moving because the two forces cancel out and equal 0 Newtons.
It is moving to the right with a force of 500 Newtons.
It is moving to the right with a force of 500 Newtons.
The answer is "It is moving to the right with a force of 500 Newtons," because the two 250 N forces are going the same direction and thus added together.
When we make diagrams or drawings of forces, we use vectors. A VECTOR is an arrow that represents the MAGNITUDE and the DIRECTION of a force. The magnitude is how strong the force is, usually in Newtons, and the direction can be expressed in north, south, east, west, left, right, up, or down.
In order to evaluate the sum of forces in a free body diagram you have to add the vectors of forces both in the horizontal and in the vertical direction. The sum of forces in all directions is called the “net force.” When forces are going in opposite directions, they should be subtracted or the value of one of the forces should be given a negative to account for the direction.
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