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Alenkasestr [34]
3 years ago
12

A racehorse is running with a uniform speed of 69 km/hr along a straightaway. What is the time it takes for the horse to cover 4

00 meters?
21 seconds

2.1 minutes

0.35 hours

27.6 hours
Physics
2 answers:
Tomtit [17]3 years ago
6 0

Answer:

21 seconds

Explanation:

First, convert km/hr to m/s.

69 km/hr × (1000 m / km) × (1 hr / 3600 s) = 19.2 m/s

Distance = rate × time

400 m = 19.2 m/s × t

t = 20.9 s

Rounded to two significant figures, it takes the horse 21 seconds.

r-ruslan [8.4K]3 years ago
5 0

Answer:

The answer to your question is: 21 seconds

Explanation:

Data

speed = v = 69 km/h

distance = d = 400 m

time = t = ?

Formula

v = d / t

t = d / v

Process

Convert 400 m to km

                                 1 km ----------------- 1000 m

                                 x     -------------------   400 m

                                x = (400 x 1) / 1000

                                x = 0.4 km

Substitution

                      t = 0.4 / 69

                      t = 0.006 h

Covert time to minutes and seconds

                     60 min -------------------- 1  h

                     x            -------------------  0.006 h

                     x = (0.006 x 60) / 1

                     x = 0.36 min

Convert time to seconds

                     1 min ------------------  60 s

                   0.36 min --------------   x

                     x = (0.36 x 60) / 1

                     x = 21.6 seconds  ≈ 21 seconds

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