Question

1. Air resistance on a flying airplane is an example of what type of friction? 2. This swimmer has to work really hard to overcome this type of friction? 3. What type of friction works against the soccer player as he kicks the soccer ball? 4. Which is correct among the following? Static friction Rolling friction> Sliding friction Static friction>Sliding friction> Rolling friction Sliding friction>Rolling friction>Static friction

Answer 1

1.  Fluid friction

2. Drag

3. Static friction

4. Static friction>Sliding friction> Rolling friction

Answer 2

Answer:

Frictions are friction drag, fluid friction, rolling friction. Static friction is greatest.

Explanation:

• When through the fluid an object moves it encounters friction called fluid friction.
• Rolling friction occurs when a cylinder or ball rolls on a surface.
• When an object moves in the air it encounters a friction drag.

Step 1:

(1) When an airplane is flying an opposing force acts on it due to air. This force is called friction drag.

So, on flying airplanes, air resistance is called friction drag.

Step 2:

(2) When a swimmer is swimming, an opposing force acts on him due to the water layer.

So, a swimmer has to overcome fluid friction.

Step 3:

(3) When a soccer player kicks the soccer ball an opposing force acts on him. This force is called rolling friction.

So, a soccer player has to encounter rolling friction.

Step 4:

(4) We know that static friction is an opposing force on an object when it is at rest. So, its value is the greatest.

Hence, the correct answer is:

Static friction>Sliding friction> Rolling friction