Worked Example: Finding Speed from Falling
Part of Gravitational Potential Energy — GCSE Physics
This required practical covers Worked Example: Finding Speed from Falling within Gravitational Potential Energy for GCSE Physics. Revise Gravitational Potential Energy in Energy for GCSE Physics with 15 exam-style questions and 6 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 9 of 16 in this topic. Revise both the method and the reason for each step, because practical questions often test understanding rather than pure recall.
Topic position
Section 9 of 16
Practice
15 questions
Recall
6 flashcards
🔬 Worked Example: Finding Speed from Falling
Question: A 2 kg ball is dropped from 5 m. Calculate its speed just before hitting the ground. (g = 10 N/kg, no air resistance)
Step 1: Calculate GPE at the top
GPE = mgh = 2 × 10 × 5 = 100 J
Step 2: Apply conservation of energy
At the bottom, all GPE has converted to KE (no air resistance)
So KE at bottom = 100 J
Step 3: Use KE equation to find speed
KE = ½mv² → 100 = ½ × 2 × v² → 100 = v²
v = √100 = 10 m/s
Quick Check: Calculate the GPE gained by a 5 kg object lifted 3 m. (g = 10 N/kg)
E_p = mgh = 5 × 10 × 3 = 150 J