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28 days ago

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The Problems: 1. Xavier starts at a position of 0 m and moves with an average speed of 0.50 m/s for 3.0 seconds. He normally mov

es faster than this but he'd just woken up. Determine his final position. 2. A hedgehog starts at a position of 0 m and moves with an average speed of 0.75 m/s for 4.0 s. Determine the final position of the hedgehog. 3. A tortoise starts at a position of 1.0 m and moves with an average speed of 1.25 m/s for 3.0 s, what is the final position of the tortoise? Cintia, in a 100 m race, has an average speed of 1.25 m/s. What was her race time? 5. Angel runs a marathon with an average speed of 5 miles/hour. How long did it take to finish?

1 answer:

Yuliya22 [3.3K]28 days ago

5 0

Answer:

(1). The position he ends up at is 1.5 m.

(2). The hedgehog's final location is 3 m.

(3). The tortoise's final location

(4). She completed the race in 80 sec.

(5). The time taken to complete is 5 hr.

Explanation:

(1). Given that,

Initial position = 0 m

Average speed = 0.50 m/s

Time = 3.0 s

We need to determine the final position

Using the average speed formula

$v_{av}=\dfrac{x_{f}+x_{i}}{t}$

Where, $x_{f}$ = final position

$x_{i}$ = Initial position

t = total time

Insert the values into the formula

$0.50=\dfrac{x_{f}+0}{3.0}$

$x_{f}=0.50\times3.0$

$x_{f}=1.5\ m$

(2). Given that,

Initial position = 0 m

Average speed = 0.75 m/s

Time = 4.0 s

We need to calculate the final position

Using the average speed formula

$v_{av}=\dfrac{x_{f}+x_{i}}{t}$

Insert the values into the formula

$0.75=\dfrac{x_{f}+0}{4.0}$

$x_{f}=0.75\times4.0$

$x_{f}=3\ m$

(3). Given that,

Average speed = 1.25 m/s

Time = 3.0 sec

Initial position = 1.0 m

We need to find the final position

Using the average speed formula

$v=\dfrac{x_{f}+x_{i}}{t}$

Insert the values into the formula

$1.25=\dfrac{x_{f}+1.0}{3.0}$

$x_{f}=1.25\times3.0-1.0$

$x_{f}=2.75\ m$

(4). Given that,

Average speed = 1.25 m/s

Distance = 100 m

We are to determine the time

Using the time formula

$t=\dfrac{d}{v}$

Insert the values into the formula

$t=\dfrac{100}{1.25}$

$t=80 sec$

(5). Given that,

Average speed = 5 miles/hr

Assuming the distance = 25 miles

We need to find the time

Using the time formula

$t=\dfrac{d}{v}$

Insert the values into the formula

$t=\dfrac{25}{5}$

$t=5\ hr$

Thus, (1). The position he ends up at is 1.5 m.

(2). The hedgehog's final location is 3 m.

(3). The tortoise's final location

(4). She completed the race in 80 sec.

(5). The time taken to complete is 5 hr.

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$|V|=\sqrt{(1.5m/s)^{2}+(-4.851m/s)^{2}$

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$\theta = tan^{-1} (\frac{-4.851m/s}{(1.5m/s)})$

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$\theta = -72.82^{o}$

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