Aptitude miscellaneous
- A gun is fired at a distance of 1.7 km from Ram and he hears the sound after 25 seconds. The speed of sound in metre per second is :
-
View Hint View Answer Discuss in Forum
Using the given formula ,
Speed = Distance Time speed of sound = 
1.7 × 1000 
m./sec. 25
Correct Option: D
Using the given formula ,
Speed = Distance Time speed of sound = 1.7 × 1000 m./sec. 25
Hence , speed of sound = 68 m./sec.
- The amount of extension in a spring is proportional to the weight hung on it. If the weight of 5 kgs produces an extension of 0.4 cm, what weight would produce an extension of 5 cm?
-
View Hint View Answer Discuss in Forum
According to the question,
The weight of 5 kgs produces an extension = 0.4 cm
∵ 0.4 cm. ≡ 5 kg.∴ 1 cm. ≡ 5 kg 0.4
Correct Option: B
According to the question,
The weight of 5 kgs produces an extension = 0.4 cm
∵ 0.4 cm. ≡ 5 kg.∴ 1 cm. ≡ 5 kg 0.4 ∴ 5 cm. ≡ 5 × 5 = 62.5 kg. 0.4
- A man walks 1 km. on 1st day, 2 km. on 2nd day, 3 km. on 3rd day and so on. The total distance the man covers in 10 days is :
-
View Hint View Answer Discuss in Forum
According to the question,
Required distance = (1 + 2 + 3 + ---- + 10) km.
We know that ,
Sum = 1 + 2 + 3 + .........+ n = n(n + 1) 
2
Correct Option: C
According to the question,
Required distance = (1 + 2 + 3 + ---- + 10) km.
We know that ,Sum = 1 + 2 + 3 + .........+ n = n(n + 1) 2
Here , n = 10Required distance = 10 × 11 = 55 km 2
