Physics Tuition Singapore – Mass,Weight and Density Misconception

Misconception 1

There is no weight acting on an astronaut who is floating in outer space while he is orbiting the Earth in a space vehicle.

Correct Concept

Weight acts on an astronaut who is floating in outer space while he is orbiting the Earth in a space vehicle. However, the space vehicle also moves at the same velocity as the astronaut. Thus, the astronaut seems to be stationary relative to the space vehicle. Although the astronaut and the space vehicle are in free fall, their horizontal speed is sufficiently large that they move around the Earth instead of falling to hit the ground

Misconception 2

Digital weighing machines found in supermarkets measure mass of objects placed on them. Readings are given in kg.

Correct Concept

Digital weighing machines found in supermarkets measure weight of objects placed on them. The machines’ scales are calibrated according to the relationship m = weight/g to give equivalent mass in kg.

Please contact Angie @ 96790479 or Mr Ong @ 98639633 if you need Secondary Pure or Combined Physics Tuition