1. Given r(square) + 7 = p, express r in terms of p.
2. The radius of a wheel is 21cm. How many revolutions did the wheel make if it travelled a distance of 66m?
Help me!!
r^2 + 7 = p
So, r^2 = p - 7
So, r = sqrt.(p - 7)............Ans 1.
radius, r = 21 cm
Circumference, C = 2 x pi x r = 2 x 21 / 7 x 21 = 126 cm = 1.26 m
Distance travelled = 66m
Number of revolutions = 66 / 1.26 = 52.38
Therefore the wheel completes 52 complete revolutions and little over the third of the 53 rd revolution....................Ans 2.
Aluminum is correct for question 1) r = â(p - 7)
2. Length of wheel with radius 21 cm = 2 * 22/7 * 21 = 132 cm
132 cm ----> 1 revolution
66 m = 6600 cm = 6600/132 = 50 revolutions
r^2+7=p
r^2=p-7
r=sqrt(p-7)
2 .r=21cm
C=2pir
=2.22/7.21
=132cm=1.32m
number of revolution=66/1.32
=50 revolutions
Comments
r^2 + 7 = p
So, r^2 = p - 7
So, r = sqrt.(p - 7)............Ans 1.
radius, r = 21 cm
Circumference, C = 2 x pi x r = 2 x 21 / 7 x 21 = 126 cm = 1.26 m
Distance travelled = 66m
Number of revolutions = 66 / 1.26 = 52.38
Therefore the wheel completes 52 complete revolutions and little over the third of the 53 rd revolution....................Ans 2.
Aluminum is correct for question 1) r = â(p - 7)
2. Length of wheel with radius 21 cm = 2 * 22/7 * 21 = 132 cm
132 cm ----> 1 revolution
66 m = 6600 cm = 6600/132 = 50 revolutions
r^2+7=p
r^2=p-7
r=sqrt(p-7)
2 .r=21cm
C=2pir
=2.22/7.21
=132cm=1.32m
number of revolution=66/1.32
=50 revolutions