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When a conducting sphere A on an insulating stand, is brought near a positively charged light sphere B hanging from a nylon thread, the sphere B is attracted to A. Which of the following conclusions about the sphere A is correct?

A Sphere A is neutral.
B Sphere A is positively charged.
C Sphere A is negatively charged.
D Sphere A is either negatively charged or neutral.

A girl is 4 m away from the plane mirror as shown in the figure. If she moves few steps closer to the mirror, what will happen to the size of image in the mirror? Consider that she can see her complete image in both the cases.


A The size of image will decrease.
B The size of image will increase.
C The size of image will be the same.
D The size of image may increase or decrease.

Which of the following about conduction is/are true?
(i) Conduction can transfer thermal energy faster in denser medium.
(ii) Conduction cannot happen together with convection.
(iii) Conduction can transfer thermal energy faster through good electrical conductors.

A(i) and (ii) only
B(i) and (iii) only
C(ii) and (iii) only
D(i), (ii) and (iii)

Refer to the given equation and select the microorganism(s) that can be correctly placed at X.


A Nitrobacter
B Penicillium
C Nitrocystis
D All of these

We should always avoid _________.

AWashing hands before and after eating food
BBrushing teeth twice a day
CFighting with friends while playing
DHelping mother in kitchen

Refer to the given word grid and select the option that can be found in it.


ATerm used for water that is fit to drink
BThe solid form of water
CName for gently moving wind
DMineral used to make watches

A word arrangement machine when given an input of words, rearranges them into a particular way as given below.
Input : happiness comes from your own actions
Step I : your happiness comes from own actions
Step II : your own happiness comes from actions
Step III : your own happiness from comes actions And Step III is the last step for the above input.
As per the rule followed in above steps, which is the last step for the given below input?
Input : "slow and steady wins the race"

AStep I
BStep II
CStep III
DStep IV

Rahul, a science teacher performed the following experiment to study the reaction between dilute sodium hydroxide and dilute sulphuric acid.

Select the correct statement(s) about the given experiment.
I. On mixing these substances, three new products will be formed, including water.
II. The chemical reaction involved is known as neutralisation reaction and is exothermic in nature.
III. The salt formed in this reaction is acidic in nature.

AII only
BII and III only
CIII only
DI and III only

Match column I with column II and select the correct option from the given codes.


A(i)–S; (ii)–Q; (iii)–R; (iv)–P
B(i)–R; (ii)–Q; (iii)–P; (iv)–S
C(i)–Q; (ii)–P; (iii)–R; (iv)–S
D(i)–R; (ii)–S; (iii)–Q; (iv)–P

A rubber ball of mass 100 g falls from a height of 4.90 m and after hitting the ground it rebounds to a height of 2.45 m. The impulse imparted to the ball by the ground if the time for which they are in contact was 0.2 s is

A1.67 N s
B2.38 N s
C3.34 N s
D0.84 N s