# Length and Time

• Created by: kpaul325
• Created on: 19-02-18 15:13
• Length and Time
• How to use a ruler.
• -Eye must be directly over mark on the scale.-To obtain an average value for a small distance multiples can be measured.
• How to use a measuring cylinder.
• -The volume of a liquid can be measured using measuring cylinder.-When making a reading the cylinder must be upright and your eye must be level with the bottom meniscus.
• The use of clocks.
• To measure very short time intervals a digital clock that can be triggered to start and stop by an electronic signal from a microphone.
• Ticker tape timers or data loggers.
• Ticker tape timers or data loggers are used to record short time intervals in motion experiments.
• Simple pendulum
• -Attach a bob to piece of string and suspend it.-Pull the bob a small distance to one side, and then release so that it oscillates to and fro through a small angle.-Find the time for the bob to make several complete oscillations.-Repeat the timing a few times for the same number of oscillations and workout the average.-The time for one oscillation is the period T. The number of complete oscillations per second is the frequency f.
• How is micrometer screw guage used?
• Used to measure very small distances Determination of the diameter 'd' of a wire Place the wire between the anvil and spindle end asindicated in the diagram.- Rotate the thimble until the wire is firmly held betweenthe anvil and the spindle.- The ratchet is provided to avoid excessive pressure onthe wire. It prevents the spindle from further movement- squashing the wire. -To take a reading:o First look at the main scale. Thishas a linear scale reading on it.The long lines are everymillimetre the shorter ones denote half a millimeter.