Speed is a measure of the distance covered by an object in a certain time, usually measured in m/s and km/h. There are several ways to measure speed, including using a speedometer, speed trap gun, stopwatch, and light gates. A distance/time graph can also be used, where the slope of the line represents speed - a constant slope means constant speed, an increasing slope means increasing speed, and a decreasing slope means decreasing speed. Several land speed records have been set by drivers trying to beat previous top speeds between two markers.
2. What basically is SPEED ?!
• Speed is a measure of the distance
covered by an object in a certain time!
• It is usually measured in m/s and km/h.
3. MEASURING SPEED
1. THE SPEEDOMETER
• A speedometer or a speed meter is a gauge that
measures and displays the instantaneous speed of a
vehicle.
• Speedometers for other vehicles have specific names
and use other means of sensing speed. For a boat, this
is a pit log. For an aircraft, this is an airspeed indicator.
4. 2. The speed trap gun
• A speed trap gun is a radar gun. When the gun is fired at
an approaching vehicle, a beam of radio waves travels
through it to the air.
• A computer in the gun compares the time difference
between sending the beam and receiving it back from
the vehicle and calculates the vehicle’s speed.
5. The 3._____ WHAT?
STOPWATCH!
• A stopwatch is a handheld timepiece designed to
measure the amount of time elapsed from a particular
time when it is activated to the time when the piece is
deactivated.
• The distance travelled from the start line to the finish line
is measured and then divided by the time measured by
the stop watch.
• What this gives? SPEED OF THE OBJECT !
6. 4. LIGHT GATES
• In a light gate, a beam of light shines onto a light-
sensitive switch. When the beam of the light gate used at
the start of a speed test is broken by an object passing
through it.
• When a beam of the light gate used at the finish of the
speed test is broken by an object passing through it, it
causes the stop watch to be stopped.
• The speed of the object is then found by dividing the
distance between the light gates by the time as
measured by the stop watch.
7. DISTANCE/TIME GRAPHS
• The distance travelled by an object over a period of time
can be plotted on a graph called a distance/time graph.
• The gradient of a distance-time graph represents the
speed of an object.
8. EXAMPLES OF DISTANCE/TIME GRAPHS
• KEY POINT:
SLOPE=SPEED
• 1. WHEN SLOPE IS
CONSTANT, SPEED IS
ALSO CONSTANT.
2. WHEN SLOPE IS
INCREASING, SPEED
ALSO INCREASES.
9. EXAMPLES OF DISTANCE/TIME GRAPHS
• KEY POINT:
SLOPE=SPEED
• 3. WHEN SLOPE IS
DECREASING, SPEED
ALSO DECREASES.
2. WHEN SLOPE IS
ZERO, SPEED IS
ZERO WHICH MEANS
THAT OBJECT IS AT
REST.
Time
10. SPEED RECORDS
• People trying to beat the
land speed record must drive
their vehicle at full speed
between two markers.
DATE SPEED/km/h DRIVER VEHICLE
15/10/97 1227.99 Andy Green Thrust SSC
4/10/83 1013.47 Richard Noble Thrust 2
23/10/70 995.85 Gary Gabelick The Blue Flame
15/11/65 960.96 Craig Breedlove Spirit Of
America
7/11/65 922.48 Art Arfan Green Monster