Physics worksheet with exercises on distance, speed, displacement, velocity, and acceleration.

I'll solve each problem step by step, carefully checking my calculations.

Problem 1: Average velocity if a ball rolls 20 metres in 10 seconds

Average velocity = distance ÷ time
Average velocity = 20 m ÷ 10 s = 2 m/s

Problem 2: Distance traveled by a car at 25 m/s for 12 minutes

First, convert 12 minutes to seconds:
12 minutes × 60 seconds/minute = 720 seconds

Distance = speed × time
Distance = 25 m/s × 720 s = 18,000 m = 18 km

Problem 3: Cyclist's average speed in m/s (30 km in 2 hours)

Convert to meters and seconds:
30 km = 30,000 m
2 hours = 2 × 3600 = 7200 seconds

Speed = distance ÷ time
Speed = 30,000 m ÷ 7200 s = 4.17 m/s (or 25/6 m/s)

Problem 4: Distance from Sun to Earth (light takes 8.5 minutes)

Convert 8.5 minutes to seconds:
8.5 × 60 = 510 seconds

Distance = speed × time
Distance = 3 × 10 m/s × 510 s = 1.53 × 10¹¹ m = 153 million km

Problem 5: Average acceleration of motorbike (0 to 30 m/s in 25s)

Acceleration = change in velocity ÷ time
Acceleration = (30 - 0) m/s ÷ 25 s = 30 ÷ 25 = 1.2 m/s²

Problem 6: Final speed of electron

Initial speed = 2500 km/s = 2,500,000 m/s
Acceleration = 1.5 × 10⁷ m/s²
Time = 0.2 s

Using v = u + at:
Final speed = 2,500,000 + (1.5 × 10⁷ × 0.2)
Final speed = 2,500,000 + 3,000,000
Final speed = 5,500,000 m/s = 5500 km/s

Problem 7: Convert 150 mph to m/s

1 mile = 1.6 km = 1600 m
1 hour = 3600 seconds

150 mph = 150 × 1600 m / 3600 s
= 240,000 / 3600
= 66.67 m/s

Problem 8: Train deceleration (55 m/s, deceleration 0.2 m/s² for 2 minutes)

Convert 2 minutes to seconds: 2 × 60 = 120 s

Using v = u + at (where a is negative for deceleration):
v = 55 + (-0.2 × 120)
v = 55 - 24
v = 31 m/s

Problem 9: Similarity and difference between distance and displacement

Similarity: Both measure how far something has moved
Difference: Distance is the total path length traveled (always positive), while displacement is the straight-line distance from start to finish with direction (can be zero or negative)

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Final Answer:

1. 2 m/s

2. 18,000 m (or 18 km)

3. 4.17 m/s (or 25/6 m/s)

4. 1.53 × 10¹¹ m (or 153 million km)

5. 1.2 m/s²

6. 5,500,000 m/s (or 5500 km/s)

7. 66.67 m/s

8. 31 m/s

9. Similarity: Both measure movement/travel
Difference: Distance is total path length (scalar, always positive); displacement is straight-line from start to end with direction (vector, can be zero/negative)