Ramp and Potential Energy?

📌 CONCEPT: The work done on an object is the product of the force applied and the displacement of the object in the direction of the force, which in this case relates to the change in its potential energy as it is lifted up the ramp.

📐 RULE / FORMULA: Work done (W) = Force (F) × Displacement (d) in the direction of the force, which can be expressed as W = F × d × cos(θ) for a force applied at an angle θ to the direction of displacement.

💡 WORKED EXAMPLE: A 5 kg block is lifted 20 m up a 30° inclined ramp. If the force applied is 50 N, calculate the work done on the block. Work done (W) = 50 N × 20 m × cos(30°) = 50 N × 20 m × 0.866 = 866 J.

⚠️ COMMON MISTAKE: Students often forget to consider the angle of the force applied and calculate the work done as just F × d, neglecting the cosine of the angle.