Biology

#### The ultimate source of organic evolution is

BiologyGeneral

- Natural selection
- Sexual reproduction
- Hormonal action
- Mutations

#### Answer:The correct answer is: Mutations

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### Related Questions to study

maths-

#### If are in A.P with common difference then sind terms]

#### If are in A.P with common difference then sind terms]

maths-General

maths-

#### The sum of all integers between 50 and 500 which are divisible by 7 is

#### The sum of all integers between 50 and 500 which are divisible by 7 is

maths-General

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#### digits )=

#### digits )=

maths-General

maths-

#### In a as shown in figure given that , then the value of is

null

#### In a as shown in figure given that , then the value of is

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null

physics-

#### A bob of mass M is suspended by a massless string of length L. The horizontal velocity at position A is just sufficient to make it reach the point B. The angle at which the speed of the bob is half of that at A, satisfies

Velocity of the bob at the point A

(i)

(i)

#### A bob of mass M is suspended by a massless string of length L. The horizontal velocity at position A is just sufficient to make it reach the point B. The angle at which the speed of the bob is half of that at A, satisfies

physics-General

Velocity of the bob at the point A

(i)

(i)

physics-

#### A particle of mass attracted with a string of length is just revolving on the vertical circle without slacking of the string. If and are speed at position and then

At

At

and at

Thus,

Also,

So,

At

and at

Thus,

Also,

So,

#### A particle of mass attracted with a string of length is just revolving on the vertical circle without slacking of the string. If and are speed at position and then

physics-General

At

At

and at

Thus,

Also,

So,

At

and at

Thus,

Also,

So,

physics-

#### A bob of mass is suspended by a massless string of length . The horizontal velocity at position is just sufficient to make it reach the point . The angle at which the speed of the bob is half of that at , satisfies

#### A bob of mass is suspended by a massless string of length . The horizontal velocity at position is just sufficient to make it reach the point . The angle at which the speed of the bob is half of that at , satisfies

physics-General

physics-

#### A body of mass is moving with a uniform speed along a circle of radius , what is the average acceleration in going from to ?

Here,

Change in velocity is going from to =

Average acceleration

Change in velocity is going from to =

Average acceleration

#### A body of mass is moving with a uniform speed along a circle of radius , what is the average acceleration in going from to ?

physics-General

Here,

Change in velocity is going from to =

Average acceleration

Change in velocity is going from to =

Average acceleration

physics-

#### Figure shows four paths for a kicked football. Ignoring the effects of air on the flight, rank the paths according to initial horizontal velocity component, highest first

$R=\frac{{u}^{2}\mathrm{sin}2\theta}{g}=\frac{2{u}_{x}{v}_{y}}{g}$
$\therefore $ Range $\propto $ horizontal initial velocity $\left({u}_{x}\right)$
In path 4 range is maximum so football possess maximum horizontal velocity in the path

#### Figure shows four paths for a kicked football. Ignoring the effects of air on the flight, rank the paths according to initial horizontal velocity component, highest first

physics-General

$R=\frac{{u}^{2}\mathrm{sin}2\theta}{g}=\frac{2{u}_{x}{v}_{y}}{g}$
$\therefore $ Range $\propto $ horizontal initial velocity $\left({u}_{x}\right)$
In path 4 range is maximum so football possess maximum horizontal velocity in the path

physics-

#### A boy throws a cricket ball from the boundary to the wicket-keeper. If the frictional force due to air cannot be ignored, the forces acting on the ball at the position X are respected by

The forces acting on the ball will be (i) in the direction opposite to its motion $ie,$ frictional force and(ii) weight $mg$.

#### A boy throws a cricket ball from the boundary to the wicket-keeper. If the frictional force due to air cannot be ignored, the forces acting on the ball at the position X are respected by

physics-General

The forces acting on the ball will be (i) in the direction opposite to its motion $ie,$ frictional force and(ii) weight $mg$.

physics-

#### A projectile $A$ is thrown at an angle of $30\xb0$ to the horizontal from point $P$. At the same time, another projectile $B$ is thrown with velocity ${v}^{2}$ upwards from the point $Q$ vertically below the highest point. For $B$ to collide with $A,\frac{{v}_{2}}{{v}_{1}}$ should be

Equating velocities along the vertical,
${v}_{2}={v}_{1}\mathrm{sin}30\xb0or\frac{{v}_{2}}{{v}_{1}}=\frac{1}{2}$

#### A projectile $A$ is thrown at an angle of $30\xb0$ to the horizontal from point $P$. At the same time, another projectile $B$ is thrown with velocity ${v}^{2}$ upwards from the point $Q$ vertically below the highest point. For $B$ to collide with $A,\frac{{v}_{2}}{{v}_{1}}$ should be

physics-General

Equating velocities along the vertical,
${v}_{2}={v}_{1}\mathrm{sin}30\xb0or\frac{{v}_{2}}{{v}_{1}}=\frac{1}{2}$

physics-

#### In a two dimensional motion of a particle, the particle moves from point , position vector . If the magnitudes of these vectors are respectively, =3 and and the angles they make with the -axis are and 15, respectively, then find the magnitude of the displacement vector

Displacement

angle between and

From figure

cos

angle between and

From figure

cos

#### In a two dimensional motion of a particle, the particle moves from point , position vector . If the magnitudes of these vectors are respectively, =3 and and the angles they make with the -axis are and 15, respectively, then find the magnitude of the displacement vector

physics-General

Displacement

angle between and

From figure

cos

angle between and

From figure

cos

physics-

#### A particle is moving on a circular path of radius with uniform velocity . The change in velocity when the particle moves from tois

Change in velocity

#### A particle is moving on a circular path of radius with uniform velocity . The change in velocity when the particle moves from tois

physics-General

Change in velocity

physics-

#### A fighter plane enters inside the enemy territory, at time with velocity and moves horizontally with constant acceleration (see figure). An enemy tank at the border, spot the plane and fire shots at an angle with the horizontal and with velocity . At what altitude of the plane it can be hit by the shot?

If it is being hit then

or

or

#### A fighter plane enters inside the enemy territory, at time with velocity and moves horizontally with constant acceleration (see figure). An enemy tank at the border, spot the plane and fire shots at an angle with the horizontal and with velocity . At what altitude of the plane it can be hit by the shot?

physics-General

If it is being hit then

or

or

physics-

#### From an inclined plane two particles are projected with same speed at same angle , one up and other down the plane as shown in figure, which of the following statements is/are correct?

So, . The acceleration of both the particles is downwards. Therefore, relative acceleration between the two I zero or relative motion between the two is uniform. The relative velocity of w.r.t. is towards, therefore collision will take place between the two in mid air.

#### From an inclined plane two particles are projected with same speed at same angle , one up and other down the plane as shown in figure, which of the following statements is/are correct?

physics-General

So, . The acceleration of both the particles is downwards. Therefore, relative acceleration between the two I zero or relative motion between the two is uniform. The relative velocity of w.r.t. is towards, therefore collision will take place between the two in mid air.