Raghav categorised the following household items into acids and bases.
Which of them are placed under the wrong category?
A 3 and 5
B 2 and 6
C 3, 4 and 5
D 2, 5 and 6
Kunal took few iron turnings and mixed them well with sulphur powder. He could separate the iron turnings with the help of a magnet. He heated the mixture for some time and tried to separate the iron turnings with the magnet but he could not. Why?
A On heating, a chemical change takes place and a new compound is formed.
B On heating, iron becomes non-magnetic hence, it is not attracted by magnet.
C On heating, a physical change takes place hence iron and sulphur gets mixed up.
D On heating, iron evaporates and only sulphur is left behind.
Animal X hatches from eggs at a place P and goes to Q to spend its life. When reproduction time comes, it goes back to P, lays eggs and then dies.
Now, select the correct option regarding it.
|A||Penguin||South pole||North pole|
|B||Siberian crane||Western Siberia||India|
|D||Arctic tern||North pole||South pole|
Two objects A and B are moving on rough surface as shown in figure. Object A has greater velocity than B then
A A experiences more frictional force than B
B B experiences more frictional force than A
C Both experience same frictional force
D Cannot be said because data is insufficient.
When we walk on sand our feet sink into it and it is difficult for us to walk but a camel can easily walk on sand because
(i) The weight of the camel is the force that is spread over the large area covered by its feet.
(ii) The pressure exerted by the camel’s body on the sand is very large.
A Only (i) is correct.
B Only (ii) is correct.
C Both (i) and (ii) are correct and (ii) is the conclusion of (i).
D Both (i) and (ii) are correct and (i) is the conclusion of (ii).
The surface area of the base of a brick X is 100 cm2. The surface area of the base of the brick Y is 250 cm2. Each brick weighs 100 N. Which of the following is correct if P1 and P2 are the pressures exerted by the bricks X and Y respectively?
A P1 = P2
B P1 > P2
C P1 < P2
D P1 = P2 = 0