Velocity v and acceleration a in two systems of units 1 and 2 are related as v 2 = n m 2 v 1 and a 2 = a 1 m n respectively. Here m and n are constants. The relations for distance and time in two systems respectively are

n 3 m 3 L 1 = L 2 and n 2 m T 1 = T 2

L 1 = n 4 m 2 L 2 and T 1 = n 2 m T 2

L 1 = n 2 m L 2 and T 1 = n 4 m 2 T 2

n 2 m L 1 = L 2 and n 4 m 2 T 1 = T 2

Match the physical quantities with their correct SI units. List-I List-II (A) Planck's constant (I) kg m s - 2 (B) Torque (II) kg - 1 m 3 (C) Weight (III) m 2 kg s - 1 (D) Specific volume (IV) kg m 2 s - 2 The correct match is

A = III , B = IV , C = I , D = II

A = II , B = IV , C = I , D = III

A = IV , B = I , C = II , D = III

A = II , B = III , C = I , D = IV

EASY

Earn 100

Define one second in terms of atomic clock.

Important Questions on Motion and Time

MEDIUM

Science>Physics>Motion and Time>Measuring Time

Velocity

(v)

and acceleration

(a)

in two systems of units

1

and

2

are related as

v_{2} = \frac{n}{m^{2}} v_{1}

and

a_{2} = \frac{a_{1}}{m n}

respectively. Here

m

and

n

are constants. The relations for distance and time in two systems respectively are

EASY

Science>Physics>Motion and Time>Measuring Time

Which of the following is not a unit of time?

EASY

Science>Physics>Motion and Time>Measuring Time

Match List I with List II

	List I		List II
A	Torque	I	$kg m^{- 1} s^{- 2}$
B	Energy density	II	$kg m s^{- 1}$
C	Pressure gradient	III	$kg m^{- 2} s^{- 2}$
D	Impulse	IV	$kg m^{2} s^{- 2}$

Choose the correct answer from the options given below :

EASY

Science>Physics>Motion and Time>Measuring Time

The distance of the Sun from earth is

1.5 \times 10^{11} m

and its angular diameter is

2000''

when observed from the earth. The diameter of the Sun will be

EASY

Science>Physics>Motion and Time>Measuring Time

The angular speed of a fly-wheel making

180 rpm

is ________

EASY

Science>Physics>Motion and Time>Measuring Time

Match the physical quantities with their correct $SI$ units.

	List-I		List-II
(A)	Planck's constant	(I)	$kg m s^{- 2}$
(B)	Torque	(II)	${kg}^{- 1} m^{3}$
(C)	Weight	(III)	$m^{2} kg s^{- 1}$
(D)	Specific volume	(IV)	$kg m^{2} s^{- 2}$

The correct match is

EASY

Science>Physics>Motion and Time>Measuring Time

If $E$ and $H$ represents the intensity of electric field and magnetizing field respectively, then the unit of $\frac{E}{H}$ will be:

EASY

Science>Physics>Motion and Time>Measuring Time

The units nanometer and picometer are related as,

EASY

Science>Physics>Motion and Time>Measuring Time

The SI unit of length is the metre. Suppose we adopt a new unit of length which equal

x

metre. The area of 1

m^{2}

expressed in terms of the new unit has a magnitude

EASY

Science>Physics>Motion and Time>Measuring Time

What is the power of a 100 W bulb in CGS units?

EASY

Science>Physics>Motion and Time>Measuring Time

A unit of area, often used in measuring land areas, is the hectare defined as

10^{4}

m^{2}

. An open-pit coal mine consumes

75

hectares of land, down to a depth of

26 m

, each year. What volume of earth, in cubic kilometre, is removed in this time?

EASY

Science>Physics>Motion and Time>Measuring Time

In a new system of units, unit of mass is 10 kg, unit of length is 1 km and unit of time is 1 min. The value of 1 watt in this new hypothetical system is

EASY

Science>Physics>Motion and Time>Measuring Time

The value of universal gas constant is