Τετράδιο Εργασιών, σελ. 184 - 187.
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Τετράδιο Εργασιών, σελ. 184 - 187.
Friction is desirable when braking a car, when we attach something to a surface that is not flat.
Friction is undesirable in machines, when we slide, in ice skating, etc.
Τετράδιο Εργασιών, σελ. 184 - 187.
The rubber band stretches more in the box with the sandpaper.
Τετράδιο Εργασιών, σελ. 184 - 187.
Friction has increased because we increased the roughness of the surfaces.
Τετράδιο Εργασιών, σελ. 184 - 187.
The friction is less when I rub my finger with soap and even less when I rub it with oil.
Τετράδιο Εργασιών, σελ. 184 - 187.
Friction is reduced because we use lubricating factors.
Τετράδιο Εργασιών, σελ. 184 - 187.
When we want friction to be high, we choose materials with a rough surface or coat the bodies with a rough surface. When we want to reduce friction, we use lubricants.
Τετράδιο Εργασιών, σελ. 184 - 187.
1. In which parts of the car is friction desirable and in which is it undesirable?
Friction is desirable in brakes to stop a car and in tires to keep it on the road. It is undesirable in a car's engine.
Τετράδιο Εργασιών, σελ. 184 - 187.
2. Γιατί πρέπει να οδηγούμε πιο προσεκτικά, όταν οι δρόμοι είναι
βρεγμένοι;
Because water between the tires and the road reduces friction.
Τετράδιο Εργασιών, σελ. 184 - 187.
They both have a rough surface to increase friction and make it easier to hold them.
3. What similarity do you notice between the glue cap and the handle of the razor? Can you comment on the type of surface at these points?
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