Friction is also a force that, when unbalanced, can change the velocity of an object. What You Will Learn â¢ The magnitude of the force of friction can vary. â¢ Kinetic friction is a force that, when unbalanced, can change the velocity of a moving object. â¢ Static friction balances an applied force and can prevent motion.
It belongs to the group of compounds. known as methylxanthines which include. theobromine (cocoa) and theophylline (tea). Because of its excellent solubility and slow rate. of degradation, caffeine can persist in aquatic. environments (Seiler et al., 2005) and has the. potential to biomagnify through the food chain. Thus, even a small amount of dissolved caffeine. in aquatic environment can concentrate over. time.
Caffeine causes calcium to be excreted in the urine and feces. For every 150 mg of caffeine ingested, about the amount in one cup of coffee, 5 mg of calcium is lost. This effect occurs even hours after the consumption of caffeine. One study of postmenopausal women found that those who consumed more than 300 mg of caffeine lost more bone in the spine than women who consumed less.