State the number of significant figures in the following : (a) 0.007 m (b) 2.64 kg (c) 0.2370 g cm-3 d) 6.320 J e) 6.032 N m-2
f) 0.0006032 m2
A calorie is a unit of heat or energy and it equals about 4.2 J where 1J = 1 kg m2 sñ2. Suppose we employ a system of units in which the unit of mass equals αkg, the unit of length equals β m, the unit of time is γ s. Show that a calorie has a magnitude 4.2 in terms of the new units.
Fill in the blanks :
c) A vehicle moving with a speed of 18 km h–1covers....m in 1 s
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Tips: -
The total surface area of a cylinder of radius r and height h is
S = 2πr (r + h).