A person jumps from a fourth-story window 15.0 m above a firefighter's safety net. The survivor stretches the net 1.0 m before coming to rest. (a) What was the average deceleration experienced by the survivor when slowed to rest by the net? (b)What would you do to make it "safer" (that is, generate a smaller deceleration): would you stiffen or loosen the net? Explain.

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A person jumps from a fourth-story window 15.0 m above a firefighter&#039;s safety net. The survivor stretches the net 1.0 m before coming to rest. (a) What was the average deceleration experienced by the survivor when slowed to rest by the net? (b)What would you do to make it &quot;safer&quot; (that is, generate a smaller deceleration): would you stiffen or loosen the net? Explain.

Theodore Schwartz · Accepted Answer

First, we need to know how fast the person was falling when he hit the net. We know how far he fell, so it is a simple task of determining the his velocity:  v=v0+at  which means we need to know how long he was falling:  d=v0+12at2  I will assume is initial velocity was zero. We can then solve the above equation for t: (keep in mind d is the distance he fell,and a is gravity, both of these are negative quantities so the negatives cancel)  t=2da≈1.75 s  plugging t into the velocity equation:  v=(−9.8)(1.75)≈17.15 ms  Now the average deceleration can be found by taking the change in velocity over the change in time. But alas, we do not have tright off hand, so we need something else What we do know is that it took 1m to stop the person. Lets

Jeffrey Jordon · Accepted Answer

Lets calculate speed just before hitting net  v0=2gh=2(9.8 m/s2)(15m)  v0=17.15 m/s  a) Person comes to rest in 1m  vf2−vr2=2ad  02−(17.15)2=2(−a)(1m)  a=147 m/s2  b) a=v022d  for smaller a ,d have to be larger  so, loosen the net

Jazz Frenia · Accepted Answer

Answer:(a) The average deceleration experienced by the survivor is a=0m/s2.(b) To make it safer and generate a smaller deceleration, we would loosen the net.Explanation:(a) Average deceleration experienced by the survivor:We can use the kinematic equation that relates acceleration (a), initial velocity (v₀), final velocity (v), and displacement (s):v2=v02+2asIn this case, the survivor starts from rest (v₀ = 0 m/s), comes to rest (v = 0 m/s), and the displacement is given as 1.0 m (s = 1.0 m).Plugging in these values, the equation becomes:02=0+2a(1.0)Simplifying the equation, we find:0=2aTherefore, the average deceleration experienced by the survivor is a=0m/s2.(b) Making it &#039;safer&#039;:To generate a smaller deceleration and make it safer, we need to increase the time it takes for the survivor to come to rest. This can be achieved by increasing the distance over which the net stretches. Therefore, we need to loosen the net.

Andre BalkonE · Accepted Answer

(a) To find the average deceleration experienced by the survivor when slowed to rest by the net, we can use the kinematic equation:vf2=vi2+2aΔxHere, vf is the final velocity (which is 0 m/s since the survivor comes to rest), vi is the initial velocity, a is the average deceleration, and Δx is the displacement.The initial velocity of the survivor can be found using the equation for free fall:vi=2ghwhere g is the acceleration due to gravity (approximately 9.8m/s2) and h is the height.Plugging in the values, we have:vi=2·9.8·15.0=294≈17.146m/sNow we can solve for the average deceleration (a):0=(17.146)2+2a(1.0)Simplifying the equation:0=294+2a2a=−294a=−2942=−147m/s2Therefore, the average deceleration experienced by the survivor when slowed to rest by the net is −147m/s2.(b) To make it &#039;safer&#039; and generate a smaller deceleration, we would need to loosen the net. A looser net would provide more give and stretch, increasing the time over which the deceleration occurs. This would result in a smaller average deceleration and reduce the impact force experienced by the survivor.

Mr Solver · Accepted Answer

Step 1:(a) To find the average deceleration experienced by the survivor when slowed to rest by the net, we can use the kinematic equation:vf2=vi2+2aΔxwhere:vf is the final velocity (0 m/s as the person comes to rest),vi is the initial velocity (which we need to find),a is the average deceleration,and Δx is the distance stretched by the net (1.0 m).The initial velocity can be calculated using the equation:vi=vf2−2aΔxSince the person jumps from a fourth-story window, we can assume the initial velocity is zero.vi=02−2a·15.0Simplifying further:0=−2a·15.0Dividing both sides by -30:0=a·15.0Therefore, a=0m/s2.The average deceleration experienced by the survivor when slowed to rest by the net is 0m/s2.Step 2:(b) We must lessen the average deceleration that the survivor experiences in order to make it &#039;safer&#039; and produce a smaller deceleration. This can be achieved by loosening the net. By making the net more elastic or increasing its flexibility, it will stretch more and provide a gentler deceleration to the survivor, reducing the impact force.Therefore, to make it safer and generate a smaller deceleration, we would loosen the net.

A person jumps from a fourth-story window 15.0 m above a firefighter's safety net. The survivor stretches the net 1.0 m before coming to rest. (a) Wha

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