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SAMPLE PAPER-SCIENCE CLASS-X SUMMATIVE ASSESSMENT-II

SUMMATIVE ASSESSMENT-II (2012-13)
SAMPLE PAPER-SCIENCE
CLASS-X TIME -3Hrs
Max.Marks90
GENERAL INSTRUCTIONS:
1. Question paper comprises of two sections, A and B.You are to attempt both the sections
2. All questions are compulsory
3. All questions of section A and all questions of section B are to be attempted separately
4. Question numbers 1 to 3 in section A are one mark questions,to be answered in one
word or one sentence
5. Question numbers 4to7 are two mark questions, to be answered in about 30 words each
6. Question numbers 8 to19 are 3 marks questions, to be answered in about 50 words
7. Question numbers 20 to24 are 5 mark questions, to be answered in about 70 words
8. Question numbers 25 to 42 in section B are MCQ based on practical skills. Each question
is a one mark question
SECTION-A
1.
Name the element which has twice as many electrons in its second shell as in its first shell. Write its electronic configuration also.
1
2.
Give common name of the plant on which Mendel performed his experiments.
1
3.
In a food chain comprising frogs, insects, birds and grass, which one of the organisms is likely to have maximum concentration of harmful non biodegradable chemicals in its body?
1
4.
Choose from the following elements whose atomic numbers are given in parentheses
H(1), He(2), C(6), F(9), Na(11), Cl(17), Mg(12)
a) Smallest element of 3rd period.
b) A noble gas.
c) A metal of 3rd period having valency 1.
d) Most non metallic element of 2nd period.
2 (more…)

Refraction – Disappearing letters

A rectangular block of glass is placed on a printed page lying on a horizontal table. what is the minimum value of u of glass so that the letters on page are not visible from any of the vertical faces of the block.

Asked Kushagr

Sample Value based questions for Class 12 Physics

Scientific and logical reasoning is a scientific value expected from students studying Physics. Use your expertise to answer the following question.
One way to make a compass is to stick a magnetized needle into a piece of cork and float it in a glass bowl full of water. The needle will align itself with the magnetic field of the earth. Since the north pole of the needle is attracted towards the north, will the needle float towards the northern side of the bowl? Defend your answer.

 

Mr. Kishan is a farmer who was staying happily in a hut made of hey and
leafy roof. It is easy for him to renovate his home with new leaves every
year as the good quality palm leaves he get free of cost and it is
environment friendly. Most of the village people are satisfied with the
same type of huts there.
But one day during heavy lightning, many of the huts were burnt to ashes
and people were sad and disappointed. Mr. Sekhar works in electricity
department and has good knowledge of current affairs. He soon reached
the spot along with his friends and pacified them and made arrangements
for their comfortable stay. The very next day the team could erect many
lightning conductors and few cavities of metal conductors and made
awareness to the villagers about lightning and the use of things installed
there. (a) What according to you, are the values displayed by Mr. Sekhar
and his friends to help Mr. Kishan and the village people? (2)
What is the principle behind working of a lightning conductor? Also by
applying Gauss theorem show that net electric field inside the metallic
cavity is zero. (2)

 

 

 

Class VI Science Question Bank

HIGHER ORDER THINKING SKILLS
FOOD: Where does it come from.
1. You are the manager of a restaurant, make a list of food items you would serve in lunch.
2. What measures are to be taken to avoid wastage of food.
3. Why are humans considered omnivores?
4. List the ingredients of any five food items you relish.
5. Form pairs of words in group A with words in group B.
A—Mustard plant, Nectar, Beetroot, carnivore, omnivore.
B– Honey, sugar, oil, humans, tiger.
6. Name two aquatic plants eaten as food.
COMPONENTS OF FOOD
1. Why is it necessary to have fresh and un-cooked vegetables and fruits in our diets.
2. Doctors advice us to drink atleast two litres of water daily why?
3. What happens (more…)

Class VIII Science Question Bank

Download a good collection of questions from Class 8 Science NCERT Textbook. The collection includes questions requiring Higher order thinking skills (HOTS

Question Bank for VIII Science

Buoyancy

A pound coin floating in mercury (Photo credit: Wikipedia)

I read in one of my chapters that when a body is immersed in a container of water (kept on a weighing machine which  reads ‘W’ at first )the apparent weight lost by the body is equal to the buoyant force, and thus the reading ‘W’ increases.

Then I came across a question like this –

A beaker containing water kept on a weighing machine weighs W. A body of weight  ‘w’ is dropped in it. It is floating & experiencing a buoyant force B, then the reading on machine is –

(a)w+W
(b)W+B
(C)W+w-B
(d)W

please give me the answer and explanation
the book says answer is (a)
but I think it is (c)

(Anwesha posted this questions)

The answer is A.

The total force acting downwards is W+w and the weighing scale is providing an equal reaction. the normal reaction offered by the weighing scale is what we get as the reading.

therefore the reading on the weighing scale must be W+w

The buoyant force is acting on the object dropped and is not contributing to the normal reaction offered by the weighing scale.

Speed of Light and Protons

If the definition of the speed of light is for massless particles, then how is a proton, having mass, accelerated to the speed of light?  This sounds like a conumdrum.

Posted Thierence

Answer:

No massive particle has not so far crossed the speed of light. Even the extremely light particles – the neutrinos – couldnot cross the speed of light. Protons have not crossed the speed of light. When it nears the speed of light, the relativistic mechanics will become prominent and the it is to be treated is different from the classical mechanics.

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