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Periyar, Chandraprabha, Etumagaram etc. are some of the famous sanctuaries of India.

Musambi, Jaffa, Blood red, Valencia.

Compound ratio = \(\frac{1}{2}\) x \(\frac{2}{3}\) x \(\frac{3}{5}\)= \(\frac{1}{5}\)

= 1: 5

Compound ratio = \(\frac{3}{4}.\frac{4}{7}\)

= \(\frac{3}{7}\) = 3 : 7

Mass of first block m₁ = 8 kg 

Mass of second block m₂ = 2 kg 

Total mass M = 8 + 2 = 10 kg 

Force applied F = 15 N 

∴ Acceleration a =\(\frac{F}{M}\)

\(\frac{15}{10}\) = 1.5 m/s² 

Force exerted on the 2 kg mass, 

F = ma 

= 2 × 1.5 = 3 N

When a spanner is having a long handle, the turning effect of the applied force is more when the distance between the fixed edge and the point of application of force is more. Hence a spanner with a long handle is preferred to tighten screws in heavy vehicles.

D) Cricket ball – more momentum

A) heavy truck

Correct option is B) 40 km/hr

Correct option is B) 11 km/s

1. After repeated use of rubber band, its stress-strain curve does not remain linear. 

2. In such case, since rubber crosses its elastic limit, there is a permanent set formed on the rubber due to which it becomes loose.

Yes. a rocket operate in free space.

T₁ = T₂ = m²₁/r + mg + = m/r (v²₁ + gr)

T₂ = L_H  = m/r(v²₁ - 2gh) + mg({r - h}/{r})

Since h = 2r

We have, T₂ = m/r(v²₁ - 4gr) + mg({r - 2r}/{r})

= m/r(v²₁ - 4gr) - mg

Therefore, T₁ - T₂ = m/r(v²₁ + gr) - m/r(v²₁ + 4gr) + mg

= 6 mg

The maximum height of a projectile is reduced due to air friction.

Jet planes use atmospheric oxygen for their fuel but rockets carry their own fuel and don’t depend on atmospheric oxygen.

(i) Newton’s 3rd law is stated by the above example

(ii) Movement of rifle getting pushed back after firing is called recoil.

(iii) The ball acquires momentum after it gets velocity.

(iv) An object continues to remain at rest or in a state of uniform motion along a straight line unless an external unbalanced force acts on it.

(v) Unbalanced force is required to produce motion in an object.

In case of normal plane surfaces, the coefficient of friction is less than unity. But, when the surfaces are so irregular that sharp minute projections and cavities exist on the surfaces, the coefficient of friction may exceed unity.

Acceleration a = {F}/{m + M}

Force experienced by m' = ma = {mF}/{M + m}

The body of mass m will just begin to slide when the force experienced by 'm' just exceeds μmg.

i.e., {Fm}/{M + m} = μmg

⇒ F = μg.(M + m)

No, A centripetal force can move a body along a circular path but it cannot produce rotational motion.

F = mv²/r, is maximum at the pole.

No, it has constant magnitude but direction changes from instant to instant.

Limiting friction has the highest magnitude and rolling friction has the lowest magnitude.

The direction of the force of friction is always opposite to the direction of external force. It may or may not be in the direction of motion.

The physical quantities which can be treated as independent of other physical quantities and are not usually defined in terms of other physical quantities are called fundamental quantities. The seven fundamental quantities are mass, length, time, electric current, temperature, luminous intensity and amount of substance.

Correct option is: (c) velocity

Dimensions of a physical quantity are the powers to which the fundamental quantities must be raised to obtain the unit of a given physical quantity.

B. High Voltage

Correct option is: (d) m/s

Correct answer is: Body at rest

The correct option is B) High voltage.

A Van de Graff generator is an electrostatic generator which uses a moving belt to accumulate electric charge on a hollow metal globe on the top of an insulated column, creating very high electric potentials. It produces very high voltage direct current (DC) electricity at low current levels.

Correct option is: (c) mass and velocity

Correct option is: (c) displacement and velocity

It is because, work done against friction along a closed path is non-zero.

volume, density, velocity

The quantities, which are derived from fundamental quantities are called derived quantities.

The physical quantities whose defining operations are based on other physical quantities are called derived quantities.

Mass, length, time, temperature, amount of substance, luminous intensity and electric current.

Correct option is: (c) Unbalanced forces

It's an unbalanced force...

When two forces acting on an object are not equal in size, we say that they are unbalanced forces.

ans: C---unbalanced force

Correct option is: (c) s = ut + 1/2 at²

Let a = acceleration with which the mass "M" moves downwards and mass "m" moves upwards.

T = tension in the string

Net downward force acting on mass M is

F = Mg - T

But F = Ma

Hence, Ma = Mg - T    ...(i)

Net upward force acting on mass 'm' is

ma = T - mg    ....(ii)

Adding (i) and (ii), we get

(M + m)a = g(M - m)

⇒ a = ({M - m}/{M + m}) x g

Putting this value in equation (ii), we have

m({M - m}/{M + m})g = T - mg

⇒ T = mg[{M - m}/{M + m} + 1]

= [{2M}/{M + m}] x g

Rolling friction is defined as the force of friction acting when a body rolls over the other body.

Rolling friction is much less than the sliding friction.

The frictional force that opposes the relative motion between the surfaces when one body slides over the other body is called sliding friction.

The force, which opposes the motion of one body over the other in contact with it, is called frictional force.

The quantities, which are derived from fundamental quantities, are called derived quantities. E.g: Velocity is derived from length and time, Charge is derived from current and time. Area is derived from length, Volume is derived from the length, etc. 

Correct option is: (c) 1 Newton.

The force of friction is opposite to the direction of applied force and along the interacting surfaces. It is generally opposite to the direction of motion provided the cause of motion is now the force of friction itself, e.g., front wheel of a bicycle moves when placed on the ground but remains stopped when lifted from the ground. In this case force of friction is in the direction of motion because cause of motion is friction itself.

In a closed system, the total linear momentum of the system remains constant or conserved.

Proof: Consider two bodies A and B of masses m₁ and m₂ moving in the same direction with uniform velocities u₁ and u₂ respectively. After the collision let their uniform velocities be v₁ and v_2. Let ‘t’ be the time of impact.

Change in momentum of A

= m₁v₁ – m₁u₁

Rate of change of momentum of A

= \(\frac{ m_1v_1-m_1μ_1}{t}\)

Change in momentum of B

= m₂v₂ – m₂u₂

Rate of change of momentum of B

= \(\frac{ m_2v_2-m_2μ_2}{t}\)

If F₁ is the force exerted by A on B then according to second law, 

F₁ = \(\frac{ m_2v_2-m_2μ_2}{t}\)(action)

If F₂ is the force exerted by B on A then

F₂ = \(\frac{ m_1v_1-m_1μ_1}{t}\) (reaction)

According to Newton’s third law, action and reaction are equal and opposite i.e.

F₁ = – F₂

 \([\frac{ m_2v_2-m_2μ_2}{t}]\) = - \(\frac{ m_1v_1-m_1μ_1}{t}\)

m₂v₂ – m₂u₂ 

= – m₁v₁ + m₁u₁

OR

m₁u₁ + m₂u₂ 

= m₁v₁ + m₂v₂

i.e., Total momentum before collision = Total momentum after collision. Hence the momentum is conserved.