Units of Time

Q.

Light year is the unit of the

1. Distance

2. Time

3. Speed

4. Intensity of light

Q.

What are the $4$ dimensions of space?

Q.

Which of the following is the largest unit of length?

1. Light-year

2. Astronomical unit

3. Parsec

4. Nothing can be decided

Q.

1 parsec is equal to

1. $3.1\times {10}^{15}m$

2. $3.1\times {10}^{-15}m$

3. $3.1\times {10}^{16}m$

4. $3.1\times {10}^{-16}m$

Q.

Question 14

The average age of children of Class VII is 12 years and 3 months express this age in seconds.

Q.

$10$ decades is equal to __________ .

Q.

The average distance between the earth and the sun is called

1. astronomical unit

2. light year

3. parallactic second

4. none of these

Q.

What is the S.I. unit of frequency?

1. Hertz
2. $\frac{1}{Hertz}$
3. Millisecond
4. Second

Q. Question 4
An object is vibrating at 50 Hertz. What is its time period?

(a) 0.02 s
(b) 2 s
(c) 0.2 s
(d) 20.0 s

Q.

Question 2 (i)
Which of the following are not correct?
(i) The basic unit of time is second.

Q.

Time has same unit in CGS, MKS and SI systems.

1. 
2. 

Q.

Explain the following
(a) What is 24 hour clock?

(b) Name two organizations which use 24 hours clock.

Q.

The S.I. unit of time is hour.

1. True
2. False

Q. Match the following MKS units of measurement to their physical quantities:

$\text{a}.$ Kilogram	$\text{i}.$ Length
$\text{b}.$ Second	$\text{ii}.$ Mass
$\text{c}.$ Metre	$\text{iii}.$ Time

1. $\text{ii}.\to \text{b}.$
   $\text{c}.\to \text{iii}.$
   $\text{a}.\to \text{i}.$
2. $\text{ii}.\to \text{a}.$
   $\text{c}.\to \text{i}.$
   $\text{b}.\to \text{iii}.$
3. $\text{i}.\to \text{b}.$
   $\text{a}.\to \text{iii}.$
   $\text{c}.\to \text{ii}.$
4. $\text{a}.\to \text{iii}.$
   $\text{c}.\to \text{i}.$
   $\text{b}.\to \text{i}.$

Q.

Which of the following is not a unit of time?

1. second

2. parsec

3. year

4. light year

Q. How many seconds are there in 12 hours?

1. 12 seconds
2. 720 seconds
3. 43200 seconds
4. 432000 seconds
5. None of these

Q. Which of the following physical quantities has same unit in all the three system of units?

1. Mass
2. Length
3. Time
4. None of these

Q. For measuring time in sports events like sprinting, $milisecond\left(ms\right)$ is a commonly used unit of time. $1ms=?$

1. ${10}^{-12}s$
2. ${10}^{-9}s$
3. None of these
4. ${10}^{-3}s$

Q. What is a leap year ?

1. $364$ days
2. $363$ days
3. $366$ days
4. $365$ days

Q. Interval between two events is called

1. Solar day
2. Hour
3. Time
4. Duration

Q.

The taken by the earth to complete one rotation about its own axis is called

1. Lunar day

2. Mean day

3. Mean solar day

Q.

Give an idea of some methods used to measure time.

Q. Time is expressed in the unit of

1. s
2. kg
3. km
4. m

Q. A simple pendulum takes 32 s to complete 20 oscillations. The time period of the pendulum is:

1. 1.6 second
2. 1.2 second
3. 1 second
4. 2 second

Q. How many seconds are there in a week?

1. 60480
2. 604800
3. 6048000
4. 6048

Q. What is the SI unit of time?

1. hour
2. second
3. minute
4. millisecond

Q.

Light year is the unit of…..

1. time

2. average intensity of sunlight in one year

3. distance

4. period of revolution of earth around sun

Q. Time is expressed in the unit of

1. s
2. m
3. kg
4. km

Q. The time taken by the earth to complete one rotation about is own axis is called

1. Solar day
2. 1 hour
3. Mean solar day
4. None

Q.

1 decade is equals to ____________ years