Question

The length of a spring varies directly with the mass of an object that is aftached to it. When a 30-gram object is attached, the

spring stretches 9 centimeters. Which equation relates the mass of the object, m, and the length of the spring, s?
vx
3
S =
10
3
3
M =
S
10
m =
1
30
S​

Answer 1

s =
`(3)/(10)` m

Explanation:

Given s varies directly with m then the equation relating them is

s = km ← k is the constant of variation

To find k use the condition s = 9 when m = 30 , thus

9 = 30k ( divide both sides by 30 )

k =
`(9)/(30)` =
`(3)/(10)`

s =
`(3)/(10)` m ← equation of variation