The pilot directs the aircraft to fly due north at 600km/h. A side-wind blows at 100km/h towards the east. What will be the aircraft's resultant velocity? (Give both its
speed and direction)

678.2 km/h and 80.54° north of east

Explanation:

From the question,

Using pythagoras theorem,

a² = b²+c² Equation 1

Where a = resultant velocity

Given: b = 600 km/h, c = 100 km/h

Substitute these values into equation 1

R² = 600²+100²

R² = 360000+10000

R² = 460000

R  = √460000

R = 678.2 km/h.

And the direction is

tanθ = 600/100

tanθ = 6

tanθ = 6

θ = tan⁻¹(6)

θ = 80.54°.

Hence the resultant velocity of the aircraft is 678.2 km/h and 80.54° north of east

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.