Explore topic-wise InterviewSolutions in .

Impulse is total effect of force on motion of a body. It’s value is equal to the product of applied force and time interval for which force is applied.
If a force is applied for a small time interval ‘dt then impulse of force. \(\vec{I}=\vec{F} \cdot d t\).

\(\vec{p}=m \vec{v}\) where m = mass of body and \(\vec{v}\) = velocity of the body.

(a) The cup gets pulled as the force of the nut and the displacement of the cup is in the same direction. 

(b) The displacement of the cup and the force applied through the ruler is in the opposite direction.

(c) Tire cup does not get displaced as two equal forces are working in opposite directions. 

(d) The work done in figure A is positive, figure B is negative and in figure C is zero.

(e) In figure A the applied force and the displacement is in the same direction, in figure B the applied force and the displacement is in the opposite direction and in figure C the applied force and displacement is perpendicular to each other.

According to this theorem, impulse of a force is equal to change in momentum due to that force.
i.e., I = \(\Delta \vec{p}=\vec{p}_{2}-\vec{p}_{1}\)

(a) It states that impulse is measured by the total change in linear momentum is Impulse = m (u - v) vector (P₂ - P₁)

(b) m = 0.1kg v = 30 m/s υ = −20 m/s

Impulse = vector(P₂ - P₁) mu - mv

Impulse = m(υ − v)s

Impulse = m (-20 – 30) = -5Ns

One kilowatt-hour is the electrical energy consumed by an electrical appliance in one hour of power 1 kilowatt when it is used for 1 hour.
1 kilowatt hour or 1 kwh
= 1 kilowatt X 1 hour
= 1000 watt X 1 hour
= 1000 joule per second x (60 x 60) seconds
= 3.6 into 10⁶ J

Boycot of foreign cloth, schools, colleges, courts by lawyers was an integral part of the Non-Cooperation Movement. 

But the Movement was gradually slow down and due to the following drawbacks.

Khadi cloth was more expensive, less durable and expensive to maintain than mill made cloth. The poor could not afford to buy it and therefore could not boycott mill made cloth for long.

Similarly boycott of institutions posed a problem. For the movement to be successful alternative Indian institutions were slow to come up. So teachers and students began tricking back to government schools. Lawyers too joined back work in government courts.

Chauri Chaura incident finally made Gandhi call off the movement, as he realized that people have not been able to understand his idea of Satyagraha.

1. Magnetic pole.

2. B = \(\sqrt{B^2_v+B^2_h}\)

But B_h = 0

∴ B = B_v

3. No. Magnetic needle align vertically

(a) Magnesium reacts with water only on boiling. 

(b) Copper does not react even with steam.

(a) Silicon is group 14 element with a valence of 4. Bromine belongs to the halogen family with a valence of 1. Hence the formula of the compound formed would be SiBr₄. 

(b) Aluminium belongs to group 13 with a valence of 3. Sulphur belongs to group 16 elements with a valence of 2. Hence the formula of the compound formed would be Al₂S₃.

(D) Student D

The correct graph is plotted by Student D .

(i) Here, n = 2, and l = 1

Since,l = 0 means a p orbital, hence the given orbital is designated as 2p.

(ii) Here, n = 2 and l = 0

Since, l = 0 means a s orbital, hence the given orbital is 2s.

(iii) Here, n = 4 and l = 3

Since, l = 3 represents f orbitals, hence the given orbital is a 4f orbital.

(iv) Here, n = 4 and l = 2

Since l = 2 means d orbital, hence the given orbital can be designated as 4d orbital.

(v) For, n = 4 and l = 1

Since l = 1 means a p-orbital, hence the given orbital is a 4p orbital.

(i) Here, n = 2, and l = 1

Since l = 1 it means a p-orbital, hence the given orbital is designated as 2p.

(ii) Here, n = 2 and l = 0

Since l = 0 means s – orbital, hence the given orbital is 2s.

(iii) Here, n = 4 and l = 3

Since, l = 3 represents f – orbital, hence the given orbital is a 4f orbital.

(iv) Here, n = 4 and l = 2

Since, l = 2 represents d – orbital, hence the given orbital is a 4d – orbital.

(v) n = 4 and l = 1

since, l = 1 means it is a p – orbital, hence the given orbital can be designated as – 4p orbital.

e ∈ R is the identity element for * if a * e = a * a = a ∀ a ∈ R or e = 2.

False

We know that, ‘e’ is called an identity element for the binary operation ‘*’ on set S, such that

a * e = e * a = a ∀ a ∈ S

Let ‘+’ be a binary operation on set N.

Now, we need to find e ∈ N such that

n + e = e + n = n ∀ n ∈ N

n + 0 = 0 + n = n ∀ n ∈ N

We observe that addition of any natural number with 0 gives the desired result but 0 ∉ N, hence 0 is not the identity element for the addition operation on N.

∴ The binary operation ‘+’ on N does not have any identity element.

A = {2,4,6,8} and B = {6,8,10,12}

A ∪ B = {2,4,6,8} ∪ {6,8,10,12}

Common elements 6, 8 should be taken once

= (2,4,6,8,10,12}

The correct option is C) Energy.

Electron volt is the measure of Energy.

Walls of the heart

Shape of smooth muscle is Spindle

Exercise increases our vital capacity and exchange of respiratory gases becomes more effective,

Cartilage reduces friction between the bones

Synovial membrane secretes synovial fluid

Capsule covers and protects the joints

joints help in the movement of bones. Joints give more flexibility to bones to move. The nature of movements varies with the nature of joints.

No. Hence it is nastic movement.

Light, gravity, water, touch, chemicals, etc. are the various stimuli which cause movements in plants.

Joints are the meeting place of two bones

If the direction of plant movement is not in accordance with the stimulus, it is called nastic movement.

Hydrotropism

Response to various is Stimuli

If the direction of plant movements is in accordance with the direction of stimulus it is called tropic movements.

Correct answer is b) Lack of oxygen in muscle cells

Skeletal system facilitating movements, maintains posture, helps in hearing, protects our internal organs from damage, produces blood cells and maintains the mineral homeostasis.

Roots grow towards gravity and the stem grows against gravity.