Question : The density of a material in CGS system of units is 4 g/cm³. In a system of units in which unit of length is 10 cm and unit of mass is 100 g, the value of density of material will be
a) 400
b) 0.04
c) 0.4
d) 40
Doubt by Sanya
Solution :
Dimensional Formula of Density
[M1L-3T0]
a=1, b=-3, c=0
a=1, b=-3, c=0
n1=4
M1=1g
L1=1cm
n2=?
M1=100g
L1=10cm
L1=10cm
n2=n1[M1/M2]a[L1/L2]b[T1/T2]c
n2=4[1/100]1[1/10]-3[T1/T2]0
n2=4[1/100][10]3×1
n2=4[1/100][10]3×1
n2=4[1000/100]
n2=4×10
n2=40
n2=4×10
n2=40
Hence, d) 40 will be the correct option.