A landing probe of mass 9.0 kg weighs 45 N on the surface of an unknown planet. Calculate the planet's gravitational field strength g.

Gravity Challenge #4 — Field Strength

g on a
mystery planet.

Gravity Easy

Problem

A landing probe of mass 9.0 kg touches down on an unknown planet, where its weight measures 45 N. Calculate the planet’s gravitational field strength \( g \).

Probe mass\( m = 9.0\ \mathrm{kg} \)
Measured weight\( W = 45\ \mathrm{N} \)
Answer inm/s² (or N/kg)

N/kg and m/s² are the same unit wearing different clothes.

Hint: the same \( W = mg \) as always — but this time \( g \) is the unknown. Divide the weight by the mass.

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m/s²

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g on amystery planet.

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g on a
mystery planet.