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Jerry the mouse is running along a straight desert road at a constant velocity of 18 m/s. If a certain Tom cat wants to capture Jerry using a net dropped from an bridge that is 15m high, how much time before Jerry is under the bridge, should Tom drop the net? s How far away from the bridge is Jerry when Tom drops the net? m

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Answer:

a) t = 1.75 s

b) x = 31.5 m

Step-by-step explanation:

a) The time at which Tom should drop the net can be found using the following equation:


y_(f) = y_(0) + v_(oy)t - (1)/(2)gt^(2)

Where:


y_(f): is the final height = 0

y₀: is the initial height = 15 m

g: is the gravity = 9.81 m/s²


v_(0y): is the initial vertical velocity of the net = 0 (it is dropped from rest)


0 = 15m - (1)/(2)9.81 m/s^(2)*t^(2)


t = \sqrt{(2*15 m)/(9.81 m/s^(2))} = 1.75 s

Hence, Tom should drop the net at 1.75 s before Jerry is under the bridge.

b) We can find the distance at which is Jerry when Tom drops the net as follows:


v = (x)/(t)


x = v*t = 18 m/s*1.75 m = 31.5 m

Then, Jerry is at 31.5 meters from the bridge when Jerry drops the net.

I hope it helps you!

User Dulara Malindu
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