CBSE Class 10 - Physics - Electricity - (Holiday Assignment) (#cbseNotes)

Electricity - (Holiday Assignment)

Q1: Two metallic wires A and B of same material are connected in parallel. Wire A has length l and radius r and wire B has length 2l and radius 2r. Compare the ratio of the total resistance of parallel combination and the resistance of wire A.

Answer:
Wire A:
Length = l
Radius = r
Area   = πr²
R₁   = ρ  x l /(πr²)

Wire B:
Length = 2l
Radius = 2r
Area = π(2r)² = 4πr²
R₂   = ρ  x 2l /(4πr²) = ρ  x l /(2πr²)

Let Rₚ = effective resistance of parallel combination
∴ 1/Rₚ = 1/R₁ + 1/R₂

1/Rₚ = (πr²)/ρl + (2πr²)/ρl

Rₚ = ρl/(3πr²)

CBSE Class 12 - Accountancy Sample Question Paper (2014-15) (#cbsePapers)

CBSE Class 12 - Accountancy Sample Question Paper (2014-15)

CBSE Class 9 - Physics - Chapter - Force and Laws of Motion (Worksheet) (#cbseNotes)

Force and Laws of Motion
(Worksheet)

Q: Fill in the blanks with suitable choice given in brackets.

1: The product of mass and velocity of a body is called __________. (momentum/force)


2: The property by the virtue of which an object tends to remain in the state of rest or of uniform motion unless acted upon by some force is called __________. (impulse/ inertia)


3: The SI unit of _________ is kilogram meters per second i.e. kg m/s (momentum/ force)


4: Momentum is a _________ (scalar/ vector) quantity and is directed along the __________ (direction/ magnitude) of velocity.


5: The total momentum of the bullet and the gun before firing would be _________ (zero/ positive / negative) because both of them ar at rest.

CBSE Class 12 - Chemistry - Chapter 1 - Solid State - Crystalline vs Amorphous Solids (#cbseNotes)

Crystalline Solids vs Amorphous Solids

Class 12 - Chemistry - Chapter 1 - Solid State

Crystalline Solids	Amorphous Solids
1. They have definite and regular geometry due to definite and orderly arrangement of atoms, ions or molecules in three dimensional space.	1. They do not have any pattern of arrangement of atoms, ions or molecules and thus, do not have any definite geometrical shape.
2. They have sharp melting points and change abruptly into liquids.	2. Amorphous solids do not have sharp melting points and do not change abruptly into liquids.

CBSE Class 9 - English Grammar - Tenses (Worksheet) (#cbseNotes)

Tenses

Worksheet (Holidays Homework)

Q Fill in the blanks in the following paragraphs with the most appropriate form of verbs.

1 My mother a)_______(do) a lot of work. She b)______(cook)food and c)________(clean) the house. Whenever I d)______(fallen) I'll, she looks after me well. She e)______(be) a religious person. She f) ______(narrate) many interesting stories from the Ramayana and the Mahabharata to us at bedtime. Right now, she is not at home.


2: I a)________. (run) for a bus when I b) ______ (hit) my foot on something on the pavement and c) _____ ( fall) over. I tried to get up but d)______( move ). I had terrible pain in my left foot. I e)_____( sprain) my ankle very badly. I was limping when some passers-by f)______(notice) me.

CBSE Class 8 - Science - CH4 Metals and Non-Metals (NCERT Exemplar Answers) (#cbseNotes)

Metals and Non-Metals 

NCERT Exemplar Answers

Multiple Choice Questions

Q1: Which of the following is not a metal?

(a) copper
(b) sulphur
(c) aluminium
(d) iron


Q2: The substance that will be flattened on beating with a hammer is

(a) crystal of iodine
(b) lump of sulphur
(c) piece of coal
(d) zinc granule

CBSE Class 8/9/10 - English Grammar - Sentence Correction - 1 (#cbseNotes) (#EnglishErrorSpotting)

Sentence Correction Worksheet - 1

English Grammar

Q: Following sentences are incorrect. Spot the error and write the correct sentence.

① Sita bought a bread.

② What is the cost of this shirt?

③ I saw beautiful sceneries in painting exhibition.

④ He is a noted dacoit.

⑤ What a luck!