Energi potensial Rumus (PE = mgh): Gratis Calculator & Examples

Cara menghitung potential energy with PE = mgh (the mgh formula). Contoh terselesaikans plus a free potential energy calculator for mass, height, and joules.

Cara menghitung Energi potensial (Quick Answer)

Near Earth’s surface, gravitational potential energy is PE = m g h (the mgh formula). Multiply mass in kilograms by g (usually 9.8 m/s²) by height in metres above your chosen zero. The answer is in joules (J).

Write PE = m × g × h.

Konversi mass to kg and height to m if needed.

Use the g value on the exam paper (9.8, 9.81, or 10).

Multiply. Check that tens of joules make sense for a few kilograms lifted about a metre.

Need a checked number now? Open the free potential energy calculator (PE = mgh) — then come back for reference-level traps and worked examples.

What Is the mgh Rumus?

mgh means mass × gravitational field strength × height. It estimates gravitational potential energy (PE or Ug) in the near-surface model used in most school problems. The formula does not care how the object got there — only how high it is relative to a chosen PE = 0 level.

Lift a book onto a shelf and you do work against gravity; that work shows up as extra PE. Drop the book and stored PE converts into kinetic energy as it falls.

PE = mgh Rearrangements

m = PE / (g h) — find mass when energy and height are known.

h = PE / (m g) — find the height that stores a given energy.

g = PE / (m h) — less common, but useful when a problem asks you to back out g.

Verify any rearrangement in the free PE calculator.

Choosing g: 9.8, 9.81, or 10

Use the value printed on the exam paper. Many courses accept g = 9.8 m/s² or g = 10 m/s² for estimates. Engineering-style problems often want 9.81. Mixing 9.8 in working and 10 in a “check” will make your answer look wrong even when the method is fine.

Tinggi and the Reference Point

Tinggi h is measured from whatever level you call PE = 0. Floor, table, ground, or the bottom of a ramp can all be valid zeros if you stay consistent. Changing the zero shifts every PE value by the same amount; energy differences between two heights stay the same.

If a ball rises from 1.0 m to 3.0 m above the floor, the change in PE uses Δh = 2.0 m, not the absolute heights alone.

Unit Traps That Break Answers

Massa in grams

Konversi grams to kilograms before multiplying (÷ 1000). Using 500 g as if it were 500 kg inflates PE by a factor of 1000.

Tinggi in centimetres

Konversi centimetres to metres (÷ 100) for SI joules. 80 cm is 0.80 m.

Berat vs mass

Berat is already a force (W = mg). Do not multiply weight by g again. If the problem gives weight in newtons, PE = W × h (same as mgh).

Usahaed Examples

Example 1: how to calculate PE for 2.0 kg lifted 1.5 m

Take g = 9.8 m/s² and the floor as PE = 0. PE = m g h = (2.0)(9.8)(1.5) = 29.4 J. Rough check with g = 10: about 30 J.

Example 2: mgh formula — find height from 25 J

A 0.50 kg ball stores 25 J relative to the ground. With g = 10 m/s², h = PE / (m g) = 25 / (0.50 × 10) = 5.0 m. With g = 9.8, h ≈ 5.1 m.

Example 3: pe = mgh with height in cm

m = 1.2 kg, h = 80 cm = 0.80 m, g = 9.8. PE = (1.2)(9.8)(0.80) = 9.408 J ≈ 9.41 J. Leaving h as 80 would wrongly give ~941 J.

Check Example 1–3 arithmetic on the potential energy calculator.

Energi potensial vs Energi kinetik

PE depends on height; kinetic energy depends on speed: KE = ½ m v². At the top of a throw, PE is high and KE is low; just before impact (ignoring air resistance), KE is high and PE is lower relative to the ground.

Compare with how to calculate kinetic energy and the

kinetic energy calculator.

Spring energy is different: elastic potential energy U = ½kx².

Kesalahan umum

Measuring h from the wrong reference or mixing two different zeros.

Leaving mass in grams or height in centimetres while reporting joules.

Using weight in newtons as if it were mass in kilograms inside PE = mgh.

Applying mgh to space-scale problems that need the full 1/r gravitational model.

Comparing PE numbers that used different g values without saying so.

Gratis Energi potensial Calculator

Use the free potential energy calculator to solve PE = mgh for energy, mass, or height with unit-aware inputs and step-by-step working.

Usaha calculator — lifting against gravity is work that shows up as PE.

Berat calculator — W = mg before PE = W h.

Gravitational force calculator — when you leave the near-surface model.

Master PE = mgh with a clear zero height and consistent SI units — then verify every homework answer on the calculator.

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