Assertion A : If A , B , C , D are four points on a semi-circular arc with a centre at O such that | A B → | = | B C → | = | C D → | . Then, A B → + A C → + A D → = 4 A O → + O B → + O C → Reason R : Polygon law of vector addition yields A B → + B C → + C D → + A D → = 4 A O → In the light of the above statements, choose the most appropriate answer from the options given below.

Both A and R are correct but R is not the correct explanation of A .

A is correct but R is not correct.

A is not correct but R is correct.

Both A and R are correct and R is the correct explanation of A .

For a body projected at an angle with the horizontal from the ground, choose the correct statement

Gravitational potential energy is maximum at the highest point.

The horizontal component of velocity is zero at highest point.

The vertical component of momentum is maximum at the highest point.

The kinetic energy (K.E.) is zero at the highest point of projectile motion.

An object moves with speed v 1 , v 2 and v 3 along a line segment A B , B C and C D respectively as shown in figure. Where A B = B C and A D = 3 A B , then average speed of the object will be :

3 v 1 v 2 v 3 v 1 v 2 + v 2 v 3 + v 3 v 1

v 1 v 2 v 3 3 v 1 v 2 + v 2 v 3 + v 3 v 1

MEDIUM

JEE Main

IMPORTANT

Earn 100

Water droplets are coming from an open tap at a particular rate. The spacing between a droplet observed at $4^{th}$ second after its fall to the next droplet is $34.3 m$ . At what rate the droplets are coming from the tap ? (Take $g = 9.8 m s^{- 2}$ )

25% studentsanswered this correctly

Important Questions on Kinematics

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 2 - Kinematics>JEE Main - 25 July 2021 Shift 2>Q 23

The relation between time

t

and distance

x

for a moving body is given as

t = m x^{2} + n x

, where

m

and

n

are constants. The retardation of the motion is: (When

v

stands for velocity)

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 2 - Kinematics>JEE Main - 25 July 2021 Shift 2>Q 24

A balloon was moving upwards with a uniform velocity of

10 m s^{- 1}

. An object of finite mass is dropped from the balloon when it was at a height of

75 m

from the ground level. The height of the balloon from the ground when object strikes the ground was around: (takes the value of

g

10 m s^{- 2}

)

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 2 - Kinematics>JEE Main - 25 July 2021 Shift 2>Q 25

The instantaneous velocity of a particle moving in a straight line is given as

v = α t + β t^{2}

, where

α

and

β

are constants. The distance travelled by the particle between

1 s

and

2 s

is:

EASY

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 2 - Kinematics>JEE Main - 25 July 2021 Shift 2>Q 26

Two vectors

\vec{X}

and

\vec{Y}

have equal magnitude. The magnitude of

(\vec{X} - \vec{Y})

n

times the magnitude of

(\vec{X} + \vec{Y})

. The angle between

\vec{X}

and

\vec{Y}

is :

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 2 - Kinematics>JEE Main - 27 July 2021 Shift 1>Q 27

$Assertion A :$ If $A, B, C, D$ are four points on a semi-circular arc with a centre at $O$ such that $| \vec{A B} | = | \vec{B C} | = | \vec{C D} | .$ Then, $\vec{A B} + \vec{A C} + \vec{A D} = 4 \vec{A O} + \vec{O B} + \vec{O C}$

$Reason R :$ Polygon law of vector addition yields $\vec{A B} + \vec{B C} + \vec{C D} + \vec{A D} = 4 \vec{A O}$

Question Image

In the light of the above statements, choose the most appropriate answer from the options given below.

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 2 - Kinematics>JEE Main - 27 July 2021 Shift 1>Q 28

A ball is thrown up with a certain velocity so that it reaches a height

h .

Find the ratio of the two different times of the ball reaching

\frac{h}{3}

in both the directions.

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 2 - Kinematics>JEE Main - 27 July 2021 Shift 2>Q 29

A particle of mass

M

originally at rest is subjected to a force whose direction is constant but magnitude varies with time according to the relation

F = F_{0} [1 - {(\frac{t - T}{T})}^{2}]

where

F_{0}

and

T

are constants. The force acts only for the time interval

2 T

. The velocity

v

of the particle after time

2 T

is:

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 2 - Kinematics>JEE Main - 27 July 2021 Shift 2>Q 30

A swimmer wants to cross a river from point $A$ to point $B$ . Line AB makes an angle of $30 °$ with the flow of the river. The magnitude of the velocity of the swimmer is the same as that of the river. The angle $θ$ with the line $A B$ should be _______ $°$ , so that the swimmer reaches point $B$ .

Question Image

Water droplets are coming from an open tap at a particular rate. The spacing between a droplet observed at 4th second after its fall to the next droplet is 34.3 m. At what rate the droplets are coming from the tap ? (Take g=9.8 m s-2)

Important Questions on Kinematics

Learn and Prepare for any exam you want !

Water droplets are coming from an open tap at a particular rate. The spacing between a droplet observed at $4^{th}$ second after its fall to the next droplet is $34.3 m$ . At what rate the droplets are coming from the tap ? (Take $g = 9.8 m s^{- 2}$ )