Question 23 of 25intermediate🔧 ApplyNumerical3 marks

Can you estimate the number of times the wheel will rotate when covering a distance of 10 metres? Hint: You can either use the circumference of the rim of the bicycle tyre or observe the movement of the bicycle tyre.

Correct Answer

To estimate wheel rotations for 10 metres: First, measure the circumference of the bicycle wheel (C = π × diameter). For a typical bicycle wheel with diameter of about 60-70 cm, circumference = π × 65 cm ≈\approx 204 cm ≈\approx 2.04 metres. Number of rotations = Total distance ÷ Circumference = 10 metres ÷ 2.04 metres ≈\approx 4.9 rotations. Therefore, the wheel will rotate approximately 5 times to cover 10 metres. The exact number depends on the actual wheel size.

Exercise: Think and Answer | Q: 5 | (Page Page 26)
For More Understanding

Explanation

The chapter introduces the concept of wheel and axle as a simple machine. This question applies mathematical concepts to understand wheel rotation. The hint suggests two methods: calculating using circumference (C = πd) or direct observation. Students learn to connect geometry with real-world applications.

Solution Steps

  1. Step 1: Measure the diameter of the bicycle wheel (typically 60-70 cm for standard bicycles)

  2. Step 2: Calculate the circumference using formula C = π × diameter

  3. Step 3: For a 65 cm diameter wheel: C = 3.14×653.14 \times 65 cm = 204.1 cm ≈\approx 2.04 metres

  4. Step 4: Divide total distance by circumference: 10 metres ÷ 2.04 metres = 4.9

  5. Step 5: Round to nearest whole number: approximately 5 rotations