how to draw a force diagram
DESCRIPTION
TRANSCRIPT
How to Draw a Force Diagram to Find the Net Force Acting on an
Object
• First, identify the object (or the system of objects) which you wish to study.
• In this example, our system will be Ms. Clanton standing still in the physical science classroom
• Next, draw a rectangle or a circle to represent the object (or system of objects) which you are studying.
• Draw a dashed circle around the object you are studying; the dashed circle represents the system you are studying. Only the object (or system) you are studying is in the dashed circle; everything else is outside.
• Next, draw a rectangle or a circle to represent the object (or system of objects) which you are studying.
• Draw a dashed circle around the object you are studying; the dashed circle represents the system you are studying. Only the object (or system) you are studying is in the dashed circle; everything else is outside.
• Then, draw everything which touches the object (or system of objects) which you are studying.
• Next, identify any forces which are acting on the object you are studying.– At least one contact
force acts at each point where the object you are studying is touched.
– Identify any forces which act at a distance (gravity, for instance).
• Next, identify any forces which are acting on the object you are studying.– At least one contact
force acts at each point where the object you are studying is touched.
– Identify any forces which act at a distance (gravity, for instance).
• Next, identify any forces which are acting on the object you are studying.– At least one contact
force acts at each point where the object you are studying is touched.
– Identify any forces which act at a distance (gravity, for instance).
Contact Force:
Support Force
• Next, identify any forces which are acting on the object you are studying.– At least one contact
force acts at each point where the object you are studying is touched.
– Identify any forces which act at a distance (gravity, for instance).
Contact Force:
Support Force
Support Force
sF
• Next, identify any forces which are acting on the object you are studying.– At least one contact
force acts at each point where the object you are studying is touched.
– Identify any forces which act at a distance (gravity, for instance).
Support Force
sF
• Next, identify any forces which are acting on the object you are studying.– At least one contact
force acts at each point where the object you are studying is touched.
– Identify any forces which act at a distance (gravity, for instance).
Support Force
sF
Gravity always pulls down on an object if
the object is at or near the surface of
the earth.
• Next, identify any forces which are acting on the object you are studying.– At least one contact
force acts at each point where the object you are studying is touched.
– Identify any forces which act at a distance (gravity, for instance).
Support Force
sF
Gravity always pulls down on an object if
the object is at or near the surface of
the earth.
Force of Gravity
gF
• Finally, you can find the net force acting on the object you are studying by adding up all of the force vectors in the diagram.
• For this example, the force vectors are equal in size but opposite in direction. So, they cancel out.
• The net force acting on the object we are studying is zero.
Support Force
sF
Force of Gravity
gF
• Finally, you can find the net force acting on the object you are studying by adding up all of the force vectors in the diagram.
• For this example, the force vectors are equal in size but opposite in direction. So, they cancel out.
• The net force acting on the object we are studying is zero.
Support Force
sF
Force of Gravity
gF
• Finally, you can find the net force acting on the object you are studying by adding up all of the force vectors in the diagram.
• For this example, the force vectors are equal in size but opposite in direction. So, they cancel out.
• The net force acting on the object we are studying is zero.
Support Force
sF
Force of Gravity
gFNet Force = 0