A body is sliding down a rough inclined plane which makes an angle of 30 degree with the horizontal. If the coefficient of friction is 0.26, the acceleration in m/s² is :

2.78

From the FBD of block, we can say that only two forces act on the line of motion

First one is mgsinθ and second one is μN (friction force).

Net force on the block will be

→ mgsinθ - μN

As per newton's second law of motion force is measured as the product of mass and acceleration.

→ ma = mgsinθ - μ(mgcosθ)

→ a = g(sinθ - μcosθ)

→ a = 9.8(sin30° - 0.25cos30°)

→ a = 9.8(1/2 - 0.25 × √3/2)

→ a = 9.8(0.5 - 0.216)

→ a = 9.8(0.284)

→ a = 2.78 m/s²