For the following questions answer them individually
The echo of the sound of a boy standing in front of a mountain is heard after 0.2 s. What is the distance of the mountain from the boy when speed of the sound is 342 m/s?
If an incident ray is reflected back along the same path in a concave mirror, then through which point does that ray pass?
Arun went 6 m from his home towards south and turnedleft to cover 8 m. Again he turned left and covered 6 m. He again turned right and covered 4 m. What wasthe direct distance from his home and which direction was he facing?
In this question, three statements are given followed by two conclusions. Choose the conclusion(s) which best fit(s) logically.
Statements:
1) Fishes live in water.
2) Tigers live in land.
3) Amphibians live both in water and on land.
Conclusions:
I. Fishes, amphibians and tigers belong to the same family.
II. Both the amphibians and tigers can live in land.
The Simple Interest on Rs.'x' for 3 years at 8% equals half the Compound Interest on Rs.4000 at 10% for 2 years. Find 'x'.
The element with atomic number 14 is hard and forms acidic oxide and a covalent halide. To which of the following categories does the element belong?
A is two years older than B who is twice as old as C. If the total of the ages of A, B and C be 27, then how old is B ?
Two trains are running in opposite directions with the same speed. If the length of each train is 120 m, and they cross each other in 12 seconds, then find the speed of each train.
Molecules are too small to be seen with naked eyes, but they can be seen with the help of-
