### Physics - Description of Motion in Two and three Dimension

#### Question - 1

If $\vec {A}, \vec B \ and \ \vec C$ represent vectors denoting the sides of a cube,the size of the cube is best given by

• A $(\vec A \cdot \vec B ) \cdot \vec C$
• B $(\vec A \times \vec B ) \cdot \vec C$
• C $(\vec A \cdot \vec B ) \times \vec C$
• D $(\vec A \times \vec B ) \times \vec C$

#### Question - 2

Choose the INCORRECT statement

• A Three vectors of different magnitude can be combined to give zero resultant
• B Two vectors of different magnitude can be combined to give zero resultant
• C A quantity whose magnitude is zero can be a vector.
• D Product of two vectors can be either a scalar or a vector

#### Question - 3

A boy is able to throw a stone vertically up to a height h.The maximum horizontal distance through which he can throw the stone is

• A $\frac{h}{2}$
• B $\frac{3h}{2}$
• C h
• D 2h

#### Question - 4

Consider the following option :
A body describing uniform circular motion experiences
A.normal acceleration
C.tangential acceleration
Mark

• A if A is correct only
• B if A and B are correct only
• C if A and C are correct only
• D if B and C are correct only

#### Question - 5

The angular frequency of the minute hand of a clock is (in rad s-1)

• A $\frac{1}{60}$
• B $\frac{\pi}{180}$
• C $\frac{\pi}{60}$
• D $\frac{\pi}{1800}$

#### Question - 6

In the wheels of a rail train,flanges are essential to provide the carriages the necessary

• A uniform velocity
• B uniform acceleration
• C centripetal force
• D centrifugal force

#### Question - 7

A uniform circular motion by a body has

• A uniform acceleration
• B  A non- uniform acceleration
• C a uniform tangential acceleration
• D a uniform tangential velocity

#### Question - 8

Which of the statements given below are correct?
The statements :
A.The direction of the velocity of a body can change when its acceleration is constant.
B.A body can have a constant velocity and still have a varying speed.
C.A body can have a constant speed and still have a varying velocity.
D.A body can have zero velocity and still be acceleration.

• A A and B only
• B B and C only
• C A,C and D only
• D C and D only

#### Question - 9

An electric bulb hangs from the roof of a train by means of a thin flexible wire.As the train goes round curved path of radius $41\sqrt(3)$ metres,the bulb shifts so that the wire makes an angle of 30° with the vertical.The speed of the train is approximately

• A 20 ms-1
• B 30 ms-1
• C 40 ms-1
• D 60 ms-1

#### Question - 10

A particle travels at constant speed,but with no restriction on its direction of motion.For this situation,the acceleration vector at any instant is

• A always perpendicular to the velocity vector
• B always in the direction of velocity vector
• C always zero
• D None of the above