Forces on inclined planes

What you'll learn

1. 1

   Forces on a slope — think of a heavy box on a ramp. Gravity pulls it down, but the ramp pushes back at an angle. 😮

2. 2

   On a frictionless ramp, which force makes the box slide down?

3. 3

   Here's the box on a 30° ramp. Weight (mg) points straight down. The ramp pushes back with the normal force (N) perpendicular to the surface. 🔽

4. 4

   A 5 kg box sits on a 20° frictionless ramp. Find the acceleration down the ramp.

5. 5

   Set the ramp angle to 30° for a 3 kg box. What is the normal force? (N = mg cosθ)

6. 6

   For a box on a 30° ramp, which is bigger: mg sin30° or mg cos30°?

7. 7

   A 4 kg box on a 25° frictionless ramp. What is the component of weight parallel to the ramp? (sin25° = 0.423, g = 9.8 m/s²)