ISC Physics Class XI Part 1>Chapter 6 - Vectors>FOR DIFFERENT COMPETITIVE EXAMINATIONS>Q 12

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IMPORTANT

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If a unit vector is represented by $0.5 \hat{i} + 0.8 \hat{j} + c \hat{k}$ then the value of $c$ is:

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Important Questions on Vectors

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IMPORTANT

ISC Physics Class XI Part 1>Chapter 6 - Vectors>FOR DIFFERENT COMPETITIVE EXAMINATIONS>Q 13

In the arrangement shown in the figure below, the ends $P$ and $Q$ of the unstretchable string, move downward with a uniform speed $u$ . Pulleys $A$ and $B$ are fixed. The mass $M$ moves upward with a speed:

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IMPORTANT

ISC Physics Class XI Part 1>Chapter 6 - Vectors>FOR DIFFERENT COMPETITIVE EXAMINATIONS>Q 14

A particle is moving towards east with a velocity of

5 m s^{- 1}

. In

10

seconds the velocity changes to

5 m s^{- 1}

towards north. Average acceleration in this time is:

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IMPORTANT

ISC Physics Class XI Part 1>Chapter 6 - Vectors>FOR DIFFERENT COMPETITIVE EXAMINATIONS>Q 15

Select the correct alternative. The coordinates of a particle moving in a plane are given by

x = a \cos p t

and

y = b \sin p t

, where

a, b

and

p

are positive constants of appropriate dimensions. Then:

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IMPORTANT

ISC Physics Class XI Part 1>Chapter 6 - Vectors>FOR DIFFERENT COMPETITIVE EXAMINATIONS>Q 16

The coordinates of a particle at time

t

are

x = 2 t + 4 t^{2}

, where

x

and

y

are in metre and

t

is in second. The acceleration of the particle at

t = 5 s

is :

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IMPORTANT

ISC Physics Class XI Part 1>Chapter 6 - Vectors>FOR DIFFERENT COMPETITIVE EXAMINATIONS>Q 17

A person aiming to reach just opposite point on bank of stream swims at speed of

0.5 m / s

at angle

120 °

with direction of flow of water. The speed of water in stream is _____.

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ISC Physics Class XI Part 1>Chapter 6 - Vectors>FOR DIFFERENT COMPETITIVE EXAMINATIONS>Q 18

A river is flowing from west to east at speed of

5 m / minute

. A man who can swim at rate of

10 m / minute

in still water is standing on south bank of river. He wants to swim across river in the shortest time. He should swim in a direction:

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IMPORTANT

ISC Physics Class XI Part 1>Chapter 6 - Vectors>FOR DIFFERENT COMPETITIVE EXAMINATIONS>Q 19

A boat which has speed of

5 km / h

in still water crosses a river of width

1 km

along the shortest possible in

15

minutes. The velocity of river water in

km / h

is