SUMMATIVE
ASSESSMENT – I
Class-IX
(SCIENCE)
Time: 3 Hrs MM: 90
Answers
Section A
1.
Intercalary meristem.
2.
The direction of velocity is along the tangent
drawn on the circle at given point.
3.
Higher yield, wider adaptability and shorter
duration of crop.
4.
Sugar on heating
melts to give liquid state, ammonium chloride sublimes on heating and change to
vapor form.
5.
Mitochondria is a
double membranous organelle which is also called as “power house of the cell”.
The outer membrane is smooth and permeable where as the inner membrane is
thrown into folds to form cristate.
6.
Apples on the tree
are in state of rest. When Harsh shook the branches of apple tree, the branches
acquired state of motion. However, apples remained in rest due to the inertia
of rest. So, some apples got separated from the branches.
7.
(a) There are
colloidal particles of mist in the forest. Light passing from the canopy of
forest is scattered and we can see the Tyndall effect.
(b) Smoke, milk.
8.
Air shows the
property of its constituents. It can be separated by physical process and no
new compound is formed.
9.
(a) She applied tincture iodine of iodine on the
wound because iodine is antiseptic.
(b)
The solute is
iodine and the solvent is alcohol.
10.
(a) Arenchyma- large air cavities.
(b) Tendon- great strength but limited flexibility.
(c) Sclereids- broad thick walled.
11.
Striated and
cardiac muscles are similar to each other in having alternate light and dark
band. Both of them have cylindrical cells.
Striated muscles are voluntary
in nature but cardiac muscles are involuntary in nature. Striated muscles are
multinucleate but cardiac muscles are uninucleate.
12.
M = 6 x 1024 kg, m = 7.4 x 1022 kg, d = 3.84 x 108 m.
F = GxMxm/d2.
F= 6.67 x 10-11 (6 x 1024) (7.4 x 1022)/ (3.84 x 108 m)2.
= 2.0 x 1020 N.
13.
u= 11m/s. s= 4 m, g
= 9.8 m/s2. S = ut + ½ at2
= -4 = 11x t x ½ x -9.8 x t2
t= 2.56s.
14.
(a) uniform motion.
(b) constant speed but after half time the direction of motion is
reversed.
(c) non-uniform motion.
15.
A force may start
motion in an object in rest. Toy train starts moving on applying force. A force
my slow down the motion. Car stops when break is applied.
A force may change the shape of an object.
Balloon change in shape on application of force.
16.
I will prefer Italian honey bee Apis mellifera
because of following reasons:
(a) Italian honey bee stays in a beehive for longer period.
(b) It breeds well.
(c) It has high honey collecting capacity.
17.
Insects pests attack the crop plants in following
three ways:
(a) They cut the root, stem and leaf.
(b) They bore into the stem and fruit.
(c) They suck the cell sap from various parts of the plant.
18.
Storage grain can
be protected from degradation and loss in weight by adopting following
preventive measures.
(a) Proper drying of the produce.
(b) Strict cleaning of the produce before storage.
(c) Fumigation using chemicals that can kill pests.
19.
(a) (i) In a
physical change a change in the physical state of substance takes place. Such
as melting of ice.
(ii)
In a chemical
change two or more substances react to form a new substance which has different
properties from original substance.
(b) (i)
Metals are good conductor of heat.
(ii) Metals
are good conductor of electricity.
20.
(a) In solids, the particles are closely
packed and their positions are fixed due to strong force of attraction.
(b) Air at sea level is compressed by the mass of air
above it. Hence, air is more dense at sea level.
(c) There are empty spaces in the packing of water
molecules in ice. On heating ice changes into water and molecules come closer.
(d) Diffusion and Brownian motion.
21. A – xylem
B-
phloem
C-Trachieds
D-vessels
E-
Xylem parenchyma
F-
Xylem Fibres
G-
Sieve tubes
F-
Companion cells
I-phloem
fibres
J-phloem
parenchyma
22.
It states that the
total momentum of an isolated system of particles remains conserved and does
not change due to mutual action-reaction forces amongst the particles of
system.
M= 10 g = 0.01 kg. u1 = 400 m/s, m=
900g= 0.90 kg, u2 = 0. Mu1 + mu2 = (m1 = m2)v
V= 0.01x 400+ 0.90 x 0/ 0.01 + 0.90 = 4.4 m/s.
23.
(a) Mass of an
object is a measure of its inertia and does not change from one place to
another. Weight = mass x acceleration. As value of g varies from place to
place, the weight of a bar of metal of given mass decrease when it is brought
to equator.
(b)
As value of g is
maximum at the poles, hence weight is more than the corresponding weight of the
object at the equator.
(c) Value of g is zero at the centre of earth.
(d) If there is no acceleration due to gravity then
any object may continue to move, even in vertically upward direction, with
constant speed.
24.
(a) Mixed cropping is raising of different
types of crops on the same farm at same time. It insures good returns to the
farmers in case of crop failure.
Inter-cropping is growing two
or more crops simultaneously in different rows in a same field in definite
pattern.
(b) The growing of different crops on a piece of land
in preplanned succession is known as crop rotation.
(c) Depending upon the duration, crop rotation is
done for different crop combinations. The availability of moisture and
irrigation facilities decide the choice of the crop be cultivated after one
harvest.
In mixed cropping the selection
of crops depends upon root pattern, water requirement, nutrient demand etc.
Section B
25.
(d)
26.
( a)
27.
(b)
28.
(a)
29.
(d)
30.
(a)
31.
(a)
32.
(b)
33.
(d)
34.
Suspension cannot
pass through the filter. True solution forms transparent solution as solute and
solvents are uniformly intermixed.
35.
The temperature
remain constant because the heat energy is used to increase the kinetic energy
of the particles.
36.
The percentage of
water absorbed by raisins = final mass- initial mass/initial mass*100. =
(y-x)/x*100.
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