Does weight increase speed?
Does weight increase speed? Although the students may know by now that weight doesn't affect speed (see Flying High, pages 4–6), they may not realise that mass does affect momentum. Weight affects speed down the ramp (the pull of gravity), but it's the mass (and friction) that affects speed after a car leaves the ramp.
How much faster will I run if I lose 10kg?
Based on this number of 2.7 seconds per kg per km and that you have lost 10 kg and are running a 10k that evaluates to: 2.7 * 10 * 10 = 270 seconds! And that time is based on weight loss alone, so with additional training you could expect to do better!