The power, P (watts) , of a car engine is proportional to the square of its speed, s ( m / s ) . When s = 15 , P = 2100 . Work out the speed (to 1 DP) when the power is 2200 watts

The speed of the car engine is 15.4m/s

Step-by-step explanation:

Given

Power = 2100; when Speed = 15

Required

Find Speed when Power = 2200

The question says power is proportional to square of speed;

Mathematically;

Represent Power with P and Speed with S

Convert proportion to an equation

Where k is proportionality constant

Make k the subject of formula

When P = 2100 and S = 15

When P = 2200 and S is unknown

Recall that

So;

becomes

Cross Multiply

Divide both sides by 2100

Take Square Roots of both sides

(Approximated)

17 1/3

step-by-step explanation:

step-by-step explanation:

you can add the two numbers and divide the result by 2. or you can find the gap between the two numbers and add half of this to the smaller number.