User Forum

Which of the given figures, represents a state of matter, that has a definite volume but no definite shape?


AP
BQ
CR
DBoth Q and R

You are busy eating your food when a spoonful of curry falls on your white shirt. You decide to go home and wash it. The moment you dip the shirt in soap water the stain _________.

ADisappears
BTurns green
CTurns red
DDoes not show any change

Fill in the blanks in the given paragraph by choosing the correct option.
Over million of years, absence of air, __p___ temperature and __q___ pressure transformed the dead organisms into ___r___ and s. One of the various constituents of s, __x___ is used in paints and road surfacing.

A
B
C
D

Refer to the given flow chart and select the incorrect option regarding organisms P, Q and R.


A Organism P could be a mammal which undergoes hibernation and is a good swimmer.
B Organism Q inhabits the area where baseball plant and golden barrel plant are of common occurrence.
C Organism R inhabits the area which gets plenty of rainfall throughout the year.
D Organisms P, Q and R show mimicry as a protective adaptation to escape their predators.

Shruti tool two similar bowls containing equal amount of water and sand. She placed both bowls in the sun for 2-3 hours. After 2-3 hours she placed both bowls inside the room for 2-3 hours.
Which of the following results she will observe from the given activity?

A Sand heats up faster than the water when kept in the sun and cools up slower than the water when placed inside the room.
B Water heats up faster than the sand when kept in the sun.
C Sand heats up faster than the water when kept in the sun and also cools faster than the water when placed inside the room.
D Water cools down faster than the sand when kept inside the room.

To investigate the conditions for rusting, following experiment was performed.

In which test tube, nails rusted most heavily and what inference can be drawn from it?

(A) Test tube P, water is needed for rusting.

(B) Test tube Q, air is needed for rusting.

(C) Test tube R, boiled water increases the rusting speed.

Which of the following statements is/are correct?
I. 5 moles of CO₂ and 5 moles of H₂O have the same mass.
II. 100 g of NH₃ has more atoms than that present in 100 g of N_2.
III. 16 g of solid sulphur contains 3.76 × 10²² molecules.

A I and II only
B II and III only
C III only
D I only

A force of 12 N acts on a block P and block Q of masses 2 kg and 4 kg respectively as shown. Given that the floor is smooth, find the force on the string between blocks P and Q.


A 2 N
B 4 N
C 8 N
D 12 N

A boy runs for 10 minutes at a uniform speed of 9 km h^-1. At what speed should he run for the next 20 minutes so that the average speed comes to 12 km h^-1?

A 13.5 km h^-1
B 10.2 km h^-1
C 8.2 km h^-1
D 7.72 km h^-1

Which of the following does not represent characteristic of a good fuel?

A It should have a high calorific value.
B Its ignition temperature should be low but well above the room temperature.
C It should have a high rate of combustion.
D It should be fairly cheap and safe to handle and transport.