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Being heavier, cricket ball has higher rate of change of momentum during motion so more force sumed.

In addition to the frictional force, a component of reaction force also provides centripetal force.

The straw paper between the China ware increases the Time of experiencing the jerk during transportation. Hence impact of force reduces on China wares

Less reaction force.

(a) Because we are unable to push (action) such a ground sufficiently hard. As a result, the force of reaction is not sufficient to helps us to move forward.

(b) Newton's third law of motion.

It is difficult to walk on a slippery road because these roads have less friction and exerting a backward force on the slippery ground becomes difficult making it difficult to walk on the slippery roads.

It becomes very difficult to walk on a slippery road because of the fact that on a slippery road, the friction is much less, and we cannot exert a backward action force on slippery ground which would produce a forward reaction force on us.

Given,

m = mass of bullet = 50 gm

= 0.050 kg

M = mass of tiger = 60 kg

v = velocity of bullet = 150 ms^-1

v = velocity of tiger

= −10 ms^-1.

(∵ It is coming from opposite direction)

n = no. bullets fired per second at the tiger so as to stop it.

p_i = 0, before firing …(i)

p_f = n(mv) + MV …(ii)

∴ From the law of conservation of momentum,

p_i = p_f

or 0 = n(mv) + MV

or n = \(-\frac{MV}{mv}\)

= \(\frac{−60×(−10)}{0.05×150}\)

= 80.

(c) on a circle 

a) This is a correct statement.

b) This statement is incorrect. 

Reason: Evaporation takes place at any temperature below its boiling point.

c) This statement is incorrect. 

Correct Statement: The inter-particle space of solids is minimum. 

Explanation: The force of attraction between the particles is also very high due to less inter-particle space. Hence solids have definite shape and a fixed volume.

d) This statement is incorrect

Correct Statement: Gases have weakest inter-particle forces.

Explanation: The inter-particle space for a gas is maximum. Hence the interparticle forces are also weak. Due to this gases have no definite shape or fixed volume. They have to be stored in a closed container always.

It is because they are electron deficient.

BaCl₂ + K₂SO₄ ➝ BaSO₄ + KCl

(iv) Assertion is wrong statement but reason is correct statement. 

(a) σ C = C : 4 (b) σ C = C : 3

σ C – H : 6 σ C – H : 6

π C = C : 3 π C = C : 2

Five structural isomers; ethyl cyclohexane, 1:1, 1:2, 1:3 and 1:4 dimethyl cyelohexane, 4 – dimethyl cyclohexane has two geometrical isomers ( cis and trans).

2 – methyl butane, (CH₃)₂ CH – CH₂ – CH₃.

Correct option is: (C) 333.15 K

We have 273.15 in the relation and not 273.16 because the triple point of water is 0.01 °C and not 0°C. In other words, 0.01 °C → 273.16 K

⇒ 0°C → 273.15 K

∴ t_c = T – 273.15.

On Celsius scale 0°C corresponds to the melting point of ice at normal pressure and the value of absolute temperature is 273.15 K. The temperature 273.16 K corresponds to the triple point of water.

Three ways to produce magnetic field are :

(i) Charge-induced magnetic field.

(ii) A current-carrying coil may do work.

(iii) The permanent magnet and an electromagnet.

Fleming's Left Hand Rule: The direction of the force which acts on the current carrying conductor placed in a magnetic field is given by Fleming's left-hand rule. It states that if the forefinger, thumb and middle finger of the left hand are stretched mutually perpendicular and the forefinger point along the direction of the external magnetic field, middle finger indicates the direction of current, then thumb points along the direction of force acting on the conductor. 

Example: When an electron enters a magnetic field at right angles, the direction of force on electron is perpendicular to the direction of magnetic field and current according to this rule.

It indicates that the magnetic field is same at all points inside the solenoid.

This property is utilised to magnetise a piece of magnetic material like soft iron when placed inside the coil.

Two ways by which the strength of an electromagnet can be increased :

Increase the amount of electric current through it. Increase the number of turns of the coil.

The scientist who discovered that sunlight consists of seven colour is Newton

1. (i) Myopia

2. (ii) 0.22 m

3. (ii) Concave lens

4. (ii) \(\frac1P\)

5. (i) Dioptre

Solution :

(a) White

(b) Blue

Light of different wavelengths (different colors) present in white light have different speed. Hence, these deviate through different angles inside the prism and get separated.

Yes, it is possible to recombine the lights of seven colours to obtain the white light again by placing another similar prism alongside the first one in the inverted position as shown below. The first prism disperses the white light into seven coloured rays. the second prism receives all the seven coloured rays from the first prism and recombines them into original white light. This is because the refration produced by the second prism is equal and opposite to that produced by the first prism. 

(a) The statement made by the student is incorrect. Positions marked 3 (yellow) and 5 (blue) are similar to the color of gold medal and the color of the sky respectively. The student is stating the nature of colors in reverse order.

(b) (i)The position marked 7 corresponds closely to the colour of a brinjal.

(ii) The position marked 1 (red) corresponds closely to the colour of 'danger' or stop signal lights.

Dispersion. White light consists of seven colours of different wavelengths. 

These components of light travel with different speeds in glass and get refracted by different angles. Due to this, splitting of white light takes place.

When light rays enter the glass prism the angle at which it bends makes the light split into its seven components because the speed of each component of light is different and due to the bending every component shows its different ability to pass through it.

Different colour of white light bends through different angles with respect to the incident light, as they pass through the glass prism. Thus, each colour emerges along a different path, forming a spectrum.

Rectangular glass slab has parallel refracting surfaces, the emergent ray is parallel to the incident ray. It slightly gets displaced laterally. While in case of prism the surface is not parallel and the light ray gets deviated at larger angle due to which it splits into its constituent colour.

Due to change in refractive index offered by the medium.

(a) X-Violet, Y-Red
(b) Different colors of white light bend through different angles with respect to the incident beam of light due to the difference in speed of light of different wavelengths.

The angle between the extended incident ray and the emergent ray is called the angle of deviation.   This is because the different colours travel through  a glass prism at different speeds.

 Correct option (A) The lens allows the eye to focus on far objects as well as near objects.   

Explanation:

Ability of the eye lens to focus both near and distant objects by adjusting its focal length is called accommodation.

The answer is (b) (ii)

• Band of color show violet at the bottom if prism is kept with BC in the bottom. 
• if prism is kept with BC in the top, then violet will be in the top followed by indigo and blue

Breaking up of the component colours of light is called dispersion. Dispersion is caused due to the difference in velocity of each colour through a medium. Scattering of light takes place due to the interaction of light and particles suspended in a medium. Rainbow-dispersion. 

The blue color of the sky, the red color of the sky at sunrise or sunset-scattering.

1. (i) Dispersion of white light by a glass prism.

2. (ii) Splitting up of white light into its component colours

3. (iii) Red

4. (iv) Violet

5. (iii) Red

The colour of sky is blue. The colour having the maximum wavelength is deviated the least. The deviation is towards the base of the prism. The white light consist of seven colours red, orange, yellow, green, blue, indigo, violet .violet is deviated the most and red the least. Blue is the third colour starting from violet. So we see that image B has based on the top hence having colours in such an order that blue is the third. Hence option B is correct.

Ciliary muscles help in changing the focal length or the curvature of the eye lens so that we can see the object clearly. This is called as the accommodation.

Planets appear to be quite big to us and can be considered to be a collection of a very large number of point sources of light. The dimming effect produced by some of the point sources is nullified by brighter effect produced by some other point sources. Thus, the overall brightness remains the same and the planets do not appear to twinkle.

(i) Since the atmosphere consists of varying densities the apparent position of the object, as seen through the hot air fluctuates. This wavering of light is an effect on atmospheric refraction.

(ii) The twinkling of a star is due to atmospheric refraction of starlight. The atmospheric refraction of light occurs in a medium oi gradually changing refractive index.

The planets are much closer to the earth and are thus seen as extended sources. A planet is considered as a collection of a large number of point-sized sources of light, the total variation in the amount of light entering our eye from all individual point sized sources will average out to zero, thereby nullifying the twinkling effect.

The planets are much closer to the earth, and are thus seen as extended sources. If we consider a plant as a collection of large number of point sized sources of light, the total variation in the amount of light entering our eye from all the individual point-sized sources will average out to zero, thereby nullifying the twinkling effect.

Planets being of larger size can be taken as a collection of large number of point-sized objects/sources of light, which nullify the twinkling effect of each other. Due to varying conditions of atmosphere, starlight undergoes multiple refraction and its path varying slightly while passing through the atmosphere. Therefore, the apparent position of star fluctuates and amount of light entering the eye changing continuously. The star sometimes appear brighter and some other time, it appears fainter. This causes twinkling of star. 

Correct option is: (D) either (A) and (B).

Fried fast food, noodles, samosa, ice cream, cool drinks are known as Junk foods.