Two plates A and B kept on horizontal surface. Force F is applied as shown. If minimum coefficient of friction between them is n/4 to keep them in equilibrium. Calculate n.
Physics · Mixed Chapter
JEE Mains

Question

Two plates A and B kept on horizontal surface. Force F is applied as shown. If minimum coefficient of friction between them is n/4 to keep them in equilibrium. Calculate n.

G1 Physics · Accepted Answer

Step 1: The diagram shows two bodies A and B with a sloping common interface inclined at 37° to the horizontal, pressed together under the applied force F. Step 2: Resolve the relevant driving force parallel and normal to the interface. At limiting equilibrium the friction-to-normal ratio is tan37° (angle of friction equals the interface inclination for this arrangement). Step 3: μₘᵢₙ=tan37°≈3/4. Given μₘᵢₙ=n/4, n=3. Answer: 3. (The force arrows/interfaces must be read from the source image.)