Figure 2. An acceleration test is staged in outer space (a) and on the ground (b). In both places, the clock and the ruler would be variable and the mass would be constant, but different results would be observed

From

Discussion on Mass in a Gravitational Field

Zhan Likui

International Journal of Physics. 2013, 1(5), 110-114 doi:10.12691/ijp-1-5-3