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Class 7
Science
Motion and Time
a car moves with a speed of 40 km h for 15 minutes...

Question:
A car moves with a speed of 40 km/h for 15 minutes and then with a speed of 60 km/h for the next 15 minutes. The total distance covered by the car is:

(i) 100 km (ii) 25 km
(iii) 15 km (iv) 10 km

Answer:

(ii) 25 km

Case 1.
Speed = 40 km/h
Time = 15 min = (15/60) hour
Distance (d₁) = speed x time = 15/60= 10 km

Case 2.
Speed = 60 km/h
Time = 15 min = (15/60)hour
Distance(d₂) = speed x time = 60*(15/60) = 15 km
Total distance (d) = (d₁ + d₂) = 10 km + 15 km = 25 km

Therefore, the total distance covered by the car = 25 km.

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Question:
A car moves with a speed of 40 km/h for 15 minutes and then with a speed of 60 km/h for the next 15 minutes. The total distance covered by the car is:

(i) 100 km (ii) 25 km
(iii) 15 km (iv) 10 km

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Question: A car moves with a speed of 40 km/h for 15 minutes and then with a speed of 60 km/h for the next 15 minutes. The total distance covered by the car is: (i) 100 km (ii) 25 km (iii) 15 km (iv) 10 km

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Question:
A car moves with a speed of 40 km/h for 15 minutes and then with a speed of 60 km/h for the next 15 minutes. The total distance covered by the car is:

(i) 100 km (ii) 25 km
(iii) 15 km (iv) 10 km