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2 years ago

7

The minute hand of a watch has a length of 1.4 cm. Find the; (a) distance moved by the tip of the minute hand from 8.13 am to 8.

49 am. (b) angle swept by the minute hand if the tip moves 8.8 mm (c)time it will bee when the minute hand sweeps the angle calculated in (b), if the minute hand started moving at 8.39 am

1 answer:

LenKa [72]2 years ago

8 0

Answer:

A). The distance covered= 5.2752 cm

B). Angle swept = 36°

C). The time = 8:45 am

Step-by-step explanation:

The watch is assumed to be a circle while the minute hand is assumed to be the radius

Radius = 1.4cm

A). From 8:13 to 8:49= 36 minutes

Recall, there is 60 minutes in a round watch.

The distance covered= 2πr*36/60

The distance covered= 2*3.14*1.4*0.6

The distance covered= 5.2752 cm

B). If distance covered is 8.8 mm

8.8 mm = 0.88cm

0.88= 2*3.14*1.4*(x/360)

0.88/(8.792)=x/360

0.1= x/360

0.1= x/360

36°= x

Angle swept = 36°

C). The time it will be if the watch started from 8:39 am and moved 36°

36/360= y/60

0.1= y/60

0.1*60= y

6 minutes= y

The time with be 8:39+6 minutes

The time = 8:45 am

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Answer:

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Step-by-step explanation:

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