Answer:

The volume V of a gas varies inversely as the pressure P on it. If the volume is 240  cm3 under pressure of 30  kg/cm2 , what pressure has to be applied to have a volume of 160  cm3 ?

The volume V varies inversely as the pressure P means when the volume increases, the pressure decreases and when the volume decreases, the pressure increases.

Now write the formula for inverse variation.

PV= k

Substitute 240 for V 30 for P in the formula and find the constant

(240)(30)=k

7200=k

Now write an equation and solve for the unknown.

We have to find the pressure when the volume is 160  cm3 .

So,

(160)(P)=7200 .

Solve for P .

P=7200160     =45

Therefore, pressure 45  kg/cm2 be applied to have a volume of 160  cm3 .

Example 2:

The length of a violin string varies inversely as the frequency of its vibrations. A violin string 14 inches long vibrates at a frequency of 450 cycles per second. Find the frequency of a 12 -inch violin string.

The length( l ) varies inversely as the frequency( f ), when the length increases, the frequency decreases and when the length decreases, the frequency increases.

Now write the formula for inverse variation.

lf=k .

Substitute 450 for f 14 for l in the formula and find the constant.

(450)(14)=k

6300=k

Now write an equation and solve for the unknown.

We have to find the frequency of 12 -inch violin string.

So,

(12)(f)=6300 .

Solve for f .

f=630012      =525

Therefore, 12 -inch violin string vibrates at a frequency of 525 cycles per second.

Step-by-step explanation:

pa brainliest na lg