Steel has a density of 8030kg/m^3. Show that a steel ball with a diameter of 5cm weighs approximately 5N
Using Weight = mass*gravitational strength
Using: Mass = density * volume
Using Volume = (4/3)pir3
Radius = 2.5cm = 0.025m
Volume = (4/3)pi0.0253 = 0.00006544 m3 (to 4 siginificant figures)
Mass = 8030 * 0.00006544 = 0.5256 kg (to 4 significant figures)
Weight = 0.5256 * 9.81 = 5.155 N (to 4 signigicant figures)
5.155 is approximately 5, therefore weight of the steel ball is approximately 5N
SH
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