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A jogger runs at an average speed of 5.30 mi/h.

(A) How fast are they running in m/s? (Report your answer to the correct number of significant figures.)
A. 2.37 m/s
B. 2.37 x 10^(-3) m/s
C. 7.58 m/s
D. 7.58 x 10^(-3) m/s
(B) How many kilometers do they run in 99.0 minutes? (Report your answer to the correct number of significant figures.)
A. 8.82 km
B. 8.8 km
C. 1.5 km
D. 15 km
(C) If they start to run at 11:15 a.m., what time is it after they cover 4.72x10^4 ft?
A. 12:45 p.m.
B. 2:00 p.m.
C. 3:30 p.m.
D. 5:15 p.m.

User Lbz
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1 Answer

5 votes

Final answer:

The jogger is running at a speed of 2.37 m/s. The jogger runs approximately 8.74 km in 99.0 minutes. The time after the jogger covers 4.72x10^4 ft is 3:30 p.m.

Step-by-step explanation:

(A) To convert the jogger's average speed from miles per hour (mi/h) to meters per second (m/s), we need to use conversion factors. Since 1 mile is equal to 1609.34 meters and 1 hour is equal to 3600 seconds, we can convert as follows:

Average speed = 5.30 mi/h * (1609.34 m / 1 mi) * (1 h / 3600 s) = 2.37 m/s (to 3 significant figures)

So, the jogger is running at a speed of 2.37 m/s.

(B) To find the distance the jogger runs in 99.0 minutes, we can use the formula Distance = Speed * Time. First, we convert 99.0 minutes to hours by dividing by 60:

Time = 99.0 min * (1 h / 60 min) = 1.65 h

Then, we can calculate the distance using the average speed:

Distance = 5.30 mi/h * 1.65 h = 8.745 mi ≈ 8.74 km (to 3 significant figures)

Therefore, the jogger runs approximately 8.74 km in 99.0 minutes.

(C) To find the time after the jogger covers 4.72x10^4 ft, we need to convert this distance to meters. Since 1 foot is equal to 0.3048 meters, we can convert as follows:

Distance = 4.72x10^4 ft * 0.3048 m / 1 ft = 14393.76 m

Since the jogger runs at a constant speed, we can use the formula Time = Distance / Speed to find the time taken:

Time = 14393.76 m / 5.30 m/s = 2719.962 s ≈ 2719.96 s

Adding this time to the starting time of 11:15 a.m., we get the new time:

11:15 a.m. + 2719.96 s = 3:30 p.m.

So, the time after the jogger covers 4.72x10^4 ft is 3:30 p.m.

User Sayakiss
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