Contact Forces
What is a contact force?
Any force that happens because two objects are touching.
What is a non-contact force?
An external force that acts on an object without physically touching it.
What is Friction?
Two surfaces rub against each other
What is the definition of internal force?
Internal forces are forces that act on an object from the inside.
What force is used to open a door?
Applied force (torsion)
What was the push force in tug of war?
pushing your feet to the ground.
What are the 2 examples of non-contact forces we learned about?
gravity, magnetism
What happens to an object when there is friction?
The object will slow down
What are the 4 internal forces we learned about?
Tension, torsion, compression, shear.
What force slows down a bicycle?
Friction
What was the pull force during tug of war?
Pulling the rope with your hands.
What is the definition of Gravity in relation to forces?
Gravity is the external force that pulls things towards each other without direct contact.
What is elastic/spring force?
Force that pulls an object back to its original shape after being stretched or compressed
What is torsion?
A force caused by twisting an object, resulting in a rotational stress within it.
What force keeps us on earth?
Gravity
What force opposes motion between two surfaces?
Friction
What is Magnetism?
Magnetism is an external force that can pull or push certain metals without direct contact.
Why is a soccer ball rolling in grass an example of friction?
Because as the ball is rolling, the grass will cause the ball to slow down.
Define compression
A force caused by an object being squeezed or pressed together, resulting in a reduction of its volume.
What is an example of compression in real life? (We talked about 2 in class)
Squeezing a lemon, a hydraulic press.
What contact force is used when pushing a box?
Applied Force
What force is responsible for keeping our planet in orbit?
Gravitational Force
What happens to the shape of an object if it is a spring or elastic force?
The object will revert to its original shape.
Define tension and provide an example (HINT: We did this outside)
a pulling force that tightens or stretches something.
During tug of war, where was the point of tension?
In the middle of the rope.