Available Answers

1. 1.

   Can we use sundial after sunset? Why?

2. 2.

   Does the length of the pendulum have any impact on the time period?

3. 3.

   Check point:

   1. Distance =
      1. Speed/Time
      2. Speed x time
      3. Time/Speed
      4. None of these
   2. The basic unit of speed is
      1. Km/min
      2. m/min
      3. Km/h
      4. m/s
   3. Which of the following is not periodic?
      1. Wilting of leaves
      2. Ripening of fruits
      3. Swinging of a pendulum
      4. Writing on a paper
   4. It can only measure time interval and not the time of the day
      1. Sand clock
      2. Sundial
      3. Pendulum clock
      4. Quartz clock
   5. Which is not the standard unit of speed?
      1. Minutes
      2. Hours
      3. Second
      4. All of these
   6. Which of these instruments measures time most accurately?
      1. Atomic clock
      2. Sundial
      3. Pendulum clock
      4. Quartz watch
4. 4.

   True-False:

   1. The speed of fast moving vehicles is measured in km/h.
   2. The speed of a car is expressed in m/s.
   3. Every object moves with a constant speed.
   4. A pendulum cannot be used for time keeping.
   5. Speed = Distance/Time
   6. A uniform motion appears as a curved line on distance time graph.
   7. The resting position of the bob of a pendulum is known as extreme position.
5. 5.

   Fill in the blanks:

   1. The ________________ in the vehicle gives the distance travelled in kilometres.
   2. The time period of a pendulum is expressed in ________________.
   3. The distance-time graph of a body in ________________ motion is a curved line.
   4. Our ancestors could tell the approximate time of the day by just looking at the ________________.
   5. The ratio of total distance travelled to total time taken is known as ________________.
   6. A body covering equal distances in ________________ intervals of ________________ then motion is said to be uniform motion.
6. 6.

   An object moves to and fro about its position of rest. What do we call this type of motion?