Contact Forces
Contact Forces: Overview
This Topic covers sub-topics such as Friction Force, Contact Forces, Fluid Friction, Pull Force, Push Force, Squeeze as Force and Its Effects and, Stretch as Force and Its Effect
Important Questions on Contact Forces
Stretching force can change the shape and size of an object. Explain with an example.
State the effect of force in, squeezing a piece of lemon between the fingers to extract its juice.
Identify the forces that are in action when a carpenter sanding some wood.
When cars drive on icy roads, the friction between the car and the road is reduced. If the friction was reduced to zero, which statement describes the motion of the car along a flat icy road?
Step 1: Cut one butterfly of the card paper. Cut the straw into two pieces. Fix them with the help of the adhesive tape at an angle on each of the wing of the butterfly as shown.
Step 2: Take a long length of a string that you can loop over a hook in the wall or a curtain rod. Pass the free ends of the thread through both the straw pieces and tie it up as shown so that when loose, the butterfly does not slip out.
Step 3: Hold both the ends of the string and pull alternately.
What force is helping the butterfly climb upwards?
Step 1: Cut one butterfly of the card paper. Cut the straw into two pieces. Fix them with the help of the adhesive tape at an angle on each of the wing of the butterfly as shown.
Step 2: Take a long length of a string that you can loop over a hook in the wall or a curtain rod. Pass the free ends of the thread through both the straw pieces and tie it up as shown so that when loose, the butterfly does not slip out.
Step 3: Hold both the ends of the string and pull alternately.
What happens at the point where the string touches the straw? Why does it not slip down when the string is held tightly?
Explain two advantages and two disadvantages of the force of friction.
Friction is a contact force.
Identify the actions involved in the following situations as push or pull, or both while moving a wheelbarrow.
Identify the actions involved in the following situation as push or pull, or both.
When a football player taking a penalty corner.
Identify the actions involved in the following situations as push or pull, or both when moving a book placed on a table.
Identify the actions involved in the following situations as push or pull, or both when drawing a bucket of water from a well.
Identify the actions involved in the following situations as push or pull, or both when a cricket ball hit by a batsman.
Identify the actions involved in the following situations as push or pull, or both while opening a drawer.
