- What is the work done on a body moving in a circular
- How many erg make a joule?
- What happens if the ozone layer covering the earth is
- Name any two fossil fuels formed from dead plant and
animal remains in the soil.
- Calculate the number of oxygen atoms in two moles of
- What is the drawback of Rutherford’s model of the
- Write any two differences between amphibians and
- Write the different kingdoms included under Whittaker’s
- A sealed cold drink tin of 400 g mass has a volume of 300
cm3. Calculate the density of the tin bottle.
- a) Why does ice float on water?
b) How is a heavy ship able
to float on water?
- a) What is the normal audible range of the human ear?
b) What is infrasonic
- Write any two causes of air pollution.
- Why does land near water bodies get colder faster at
a) Explain the difference between the symbols 4 P and
b) Predict the formulae for the compounds that contain the
following pairs of ions:
(i) Fe3+ and SO42-
(ii) Na+ and CO32-
c) Calculate the molecular mass of aspirin,
C9H8O4 (atomic mass: H = 1, C =
12, O = 16).
Convert the following into moles:
(i) 150 g of CaCO3
(ii) 16 g of O2
(iii) 3.011 × 1024 atoms of sulphur
(atomic mass: Ca = 40, C = 12, O = 16, S = 32)
The diagram given here shows some characteristic features of
two divisions. Identify them and write any three differences
- Describe the AIDS disease.
- Describe any three modes of entry of microbes that decide
the site of manifestation within an organ or tissue.
- Explain the following terms:
b) Immune system
a) An object of mass 40 kg is raised to a height of 5 m
above the ground. What is its potential
b) If the object is allowed
to fall, find its kinetic energy:
When it is half-way down
before it strikes the ground
- Give three examples where multiple reflection of sound is
a) What is an echo?
b) At least how far should
somebody stand from a surface that reflects sound so that she can
hear an echo when she claps her hands (take velocity of sound = 340
c) How is this distance affected when the temperature of the air
a) Calculate the number of electrons in a
P3- ion if the atomic weight of phosphorus is
31 u and its atomic number is 15.
b) What is the difference between 12C, 13C
and 14C, and what do they represent?
c) An element is represented as
. Write its electronic configuration. What valency does it exhibit?
d) Describe the features of energy levels proposed by
a) How many nucleons are present in an atom of nobelium,
? How many electrons are present?
How many nucleons can be considered as
b) Explain Thomson’s model of the
are present in the ratio of 1:1. Calculate the average atomic
mass of an atom of Br. (1)
What type of energy transformation that takes place in the
following? (a) Motor (b) Florescent lamp (c) Generator (d) Woman
drawing water from a well with a bucket (e) Waterfall
a) Define power. What is the commercial unit of
b) If there are three bulbs of 100 W each, and two
motors of 1500 W each in a house, and all of them are used for five
hours every day, then find the cost of the electricity consumed for
the month of April, at Rs 5/- per unit.
Describe the following
a) Global warming
b) Depletion of ozone layer
c) Carbon cycle
d) Physical and biological nitrogen fixation
e) Oxygen cycle
Draw a schematic representation of the water
cycle. Also explain how water is replenished in the ground and in
This plant shows a dominant gametophyte stage. Identify the
division to which it belongs.
Here is an animal in which the brood
pouch is seen in males. Identify the class to which this animal
Identify the organisms that show hearts A, B and C.
a) A-Whale, B- Ostrich,C-Salamander
b) A-Salamander, B- Whale, C-Rohu
c) A-Rohu, B- Salamander, C-Ostrich
d) A-Ostrich, B-Rohu, C-Whale
How many teeth does a peacock have?
Identify the characteristic feature of this animal that
placed it under the phylum Annelida.
Segmented externally by grooves and internally by septa
a) Absence of exoskeleton
b) True coelom
c) Segmental nephridia
John observed a flatworm under a microscope, and made the
following observations, except one. Identify it.
a) Skeleton, circulatory and respiratory
systems are absent
b) Coelom is absent
c) Suckers and hooks are present
d) Alimentary canal has mouth and anus
The condition for which a solid sinks in a liquid is:
a) The density of the solid is
less than that of the liquid
b) The density of the solid is
greater than that of the liquid
c) The density of the solid is
equal to that of the liquid
d) The volume of water displaced
is greater than the volume of the solid
A car lift in a workshop or garage works on:
a) Pascal's law
b) Archimedes' principle
c) Laws of floatation
d) Bernoulli's principle
The units of density and relative density are ____ and ____,
c) g/cm3, no units
d) No unit, kg/m3
A force of 50 N acts on a surface of area 400
cm2.The pressure exerted on the surface is:
a) 1250 Pa
b) 0.125 Pa
c) 125 Pa
d) 125 dyne/cm2
Which of the following experiences the greater upthrust?
a) air balloon when immersed in
b) A wooden block floating on
c) An iron nail when immersed in
d) A copper coin when immersed in
Which of the following properties of a solid tells us
whether it can float or sink when immersed in water?
The persistence of sound in an auditorium is the result
a) Single reflection of sound
b) Single refraction of sound
c) Repeated refraction of
d) Repeated reflection of
A tuning fork vibrates 256 times a
second, and the sound propagates at 340 m/s. The length of each
wave produced by the fork is approximately ___ m.
Several pebbles are dropped into a trough
containing water at the rate of one pebble per second. Each pebble
generates a ripple in the trough. The frequency of the ripples is
A sound wave is incident on a cement wall
in a room at an angle of 25°. The wave reflects at an angle of
___ from the plane of the wall.