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3 years ago

7

In a football game, one team kicks off to the other. At the moment the receiver catches the ball, he is 40 yards from the neares

t tackler. The receiver runs left to right at a speed of 10 yards per second (10 y/s). The tackler runs right to left at a speed of 6 yards per second.
How long does it take before they collide? _____

How far does the receiver go? _____________________

2 answers:

Talja [164]3 years ago

8 0

The answer is hopefully if i'm correct is 5 or 6 seconds

Nikitich [7]3 years ago

6 0

Answer:

Part a)

$\delta t = 2.5 s$

Part b)

$d = 25 yards$

Explanation:

Speed of the receiver is 10 yards per second towards right

Speed of the tackler is 6 yards per second towards left

So here we have net relative speed of the two towards each other is given as

$v_{12} = v_1 - v_2$

$v_{12} = 10 - (-6) = 16 yards/s$

now we know that the distance between receiver and tackler initially is 40 Yards

Part a)

so the time taken by two to collide is given as

$\delta t = \frac{\Delta x}{v}$

$\delta t = \frac{40}{16}$

$\delta t = 2.5 s$

Part b)

Distance moved by the receiver in t = 2.5 s

$d = vt$

$d = 10 (2.5)$

$d = 25 yards$

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