Question

"1.    The wheels of a car are of diameter 80 cm each. How many complete revolutions does each wheel make in 10 minutes when the car is travelling at a speed of 66 km per hour?

2.     Find the area of the sector of a circle with radius 4 cm and of angle 30°. Also, find the area of the corresponding major sector (Use π = 3.14)"

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Answer 1

Answer:

a)

perimeter of circle= 2πr= 2×3.14×40cm

distance travelled by car= speed × time= 11km(change 10 min to hr)

now let no of revolution = n

so,

n×perimeter of wheel = distance by car

so,

n×2×3.14×40= 1100000cm

n=4379

b)

major part will contain angle 360-30= 330

so area of sector is angle/360×πr²=330/360×3.14×4×4=46.05