![background image](/i/bentley/147970/bentley-motors-t/h/bentley-motors-t-017.png)
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2.1 Mode of operation
Always place the distance covered opposite the reference mark serving as the
basis for the calculation:
●
on
SECONDS
if the interval is measured in seconds;
●
on
MINUTES
if the interval is measured in minutes;
●
on
HOURS
if the interval is measured in hours.
n .B. t he time measured using the chronograph must be converted if necessary
into seconds, minutes or hours to correspond to one of the three reference
marks on the fixed scale. For example: 1 minute 20 seconds = 80 seconds; 1 hour
10 minutes = 70 minutes, etc.
Example 1:
if a vehicle covers 1.5 km (or 1.5 miles) in 45
seconds, what is its average speed?
Solution: place the figure 1.5 (distance covered) on the
SECONDS
mark of the fixed scale, then read off the result
opposite the figure 45 (interval measured); in this case
120 km/h (or 120 mph).
Example 2:
if a vehicle covers 4.5 km (or 4.5 miles) in 1
minute 30 seconds (= 90 seconds), what is its average speed?
Solution: place the figure 4.5 (distance covered) on the
SECONDS
mark on the fixed scale, then read off the result
opposite the figure 90 (= 1 minute 30 seconds); in this case
180 km/h (or 180 mph).
Example 3:
if a vehicle covers 50 km (or 50 miles) in 15
minutes, what is its average speed?
Solution: place the figure 50 (distance traveled) on the
MINUTES
mark on the fixed scale, then read off the result
opposite the figure 15; in this case 200 km/h (or 200 mph).
Example 4:
if a vehicle covers 800 km (or 800 miles) in 5
hours, what is its average speed?
Solution: place the figure 800 (distance covered) on the
HOURS
mark on the fixed scale, then read off the result
opposite the figure 5; in this case 160 km/h (or 160 mph).