Fizika 7 Klass Kirik Sila Treniia Dostatochnyi Uroven -

Note: For constant speed, the pulling force must equal the friction force. Task : To pull a sled at a constant speed, a force of is applied. Find the coefficient of friction. Solution : 4. Key Takeaways for Kirik's Methodology

: Prevents an object from starting its motion. It is equal in magnitude to the applied pulling force until the maximum threshold is reached.

Рабочие программы по физике 7-11 класс - УчМет fizika 7 klass kirik sila treniia dostatochnyi uroven

"Sufficient level" problems often require 2–3 steps of calculation, such as finding the mass of an object given the friction force and coefficient, or determining the coefficient of friction from experimental data. Task : A wooden crate with a mass of

is pulled along a horizontal floor. The coefficient of friction is Note: For constant speed, the pulling force must

. What force is required to move the crate at a constant speed? : Calculate gravity force: Calculate friction:

: For sliding friction, the force is proportional to the normal force (weight on a horizontal surface): Ffr=μ⋅Ncap F sub f r end-sub equals mu center dot cap N Ffrcap F sub f r end-sub is the friction force (Newtons, Solution : 4

: Occurs when a body rolls (e.g., a wheel); it is usually much smaller than sliding friction for the same materials. 3. Example Problems (Sufficient Level)