Time

Q.

Rearrange the following words and phrases to form meaningful sentences : a) wear / these / people / a majority / of / days / a watch b) time / it / in / measures / seconds / and / hours / minutes c) shapes / different / a wristwatch / sizes / and / is available / in d) like / digital / while / prefer / wristwatches / mechanical ones / others / some people

Q. Name a device which is used ti measure very small intervals of time in laboratory or in sports.

Q.

What is the time period of a pendulum clock?

Q. $1$ hour is equivalent to:

1. $\frac{1}{60}\text{day}$
2. $3600\text{seconds}$
3. $60\text{minutes}$
4. $\frac{1}{24}\text{day}$

Q.

What Is Time According To Physics?

Q. An iron ball and a wooden ball of same radius are released from a height ‘h’ in vacuum. Which of the two balls would take more time to reach the ground?

1. Wooden ball
2. None of these
3. Iron ball
4. Both would take the same time

Q.

What is time? Name the device used to measure time.

Q. Which of the following instrument(s) is/are used to measure time?

1. Speedometer
2. Digital clocks
3. Quartz clocks
4. Sun dial

Q. Match the following unit conversions:
(m: metre, cm: centimetre, mm: millimetre and km: kilometre)

1. 10 mm
2. 1 m
3. 1000 m
4. 10 cm

Q.

Encircle the odd one out and give reasons:

Sundial, pendulum clock, stopwatch, measuring tape, quartz watch.

Q.

Name a device that is used to measure the time taken by athletes in a 100 m race at Olympic games.

Q.

A _____________ can measure time interval of $\frac{1}{10}$th of a second.

Q. Name two devices used to measure time.

Q. Driving at a speed of 60 miles per hour, how long would it take to drive 240 miles?

1. 4.5 hours
2. 4 hours
3. 3.5 hours
4. 5 hours

Q. Which of the following is incorrect?

1. 10 years = 10 decade

2. 1 mean solar day = 24 hours

3. 1 minute = 100 seconds

4. 1 hour = 60 minutes

Q. One hour is equivalent to 3600 seconds.

1. True
2. False

Q. The SI unit of time is second.

1. False
2. True

Q. Two hours is equivalent to .

1. 1200 minutes
2. 120 minutes
3. 60 minutes

Q.

The distance-time graph for a uniform motion is a ____.

1. straight line having ${45}^0$ to X-axis

2. curved line

3. straight line parallel to Y-axis

4. straight line parallel to X-axis

Q. If an airliner is flying east at 400 miles per hour, what distance will it have travelled after 3 hours?

1. 1, 200 miles
2. 133.33 miles
3. 800 miles
4. 4, 000 miles

Q. The distance-time graph of a body is a straight line parallel to the X-axis. What does this imply?

1. The body is in uniform motion.
2. The body is at rest.
3. The body is in non-uniform motion.
4. The body is in periodic motion.

Q. An aeroplane is moving on a circular path with a speed $250km{h}^{-1}$. What is the change in velocity in half revolution?

1. $125km{h}^{-1}$
2. $250km{h}^{-1}$
3. 0
4. $500km{h}^{-1}$

Q. A simple pendulum takes 32 sec to complete 20 oscillations. What is the time period of the pendulum?

1. 6.25 seconds
2. 16 seconds
3. 0.625 seconds
4. 1.6 seconds

Q. Which of the following insrtuments measures time most accurately?

(a) sundial
(b) quartz watch
(c) pendulum clock
(d) watch with balance wheel

Q. Which of the following is/are not correct?

(i) The basic unit of time is second.
(ii) Distance between two cities is measured in kilometres.
(iii) The speed of a train is expressed in m/h.

1. ii and iii only
   
2. iii only
   
3. i and ii only
   
4. i only