The acceleration due to gravity on the surface of planet Q is three times that on Earth. Thus an object with a measured mass of 5.0 kg on Earth would have what mass on planet Q

Mass = 5.0 kg.

Explanation:

Mass can be defined as a measure of the amount of matter an object or a body comprises of. The standard unit of measurement of the mass of an object or a body is kilograms.

Irrespective of the location of an object or a body at a given moment in time, the mass (amount of matter that they're made up of) is constant. This ultimately implies that, whether you're in the moon, space, earth or any other place, your mass remains the same (constant).

In this scenario, the acceleration due to gravity on the surface of planet Q is three times that on Earth. Thus, an object with a measured mass of 5.0 kg on Earth would have a mass of 5.0 kg on planet Q because the mass of an object remains the same irrespective of the planet.