SRL Archive - Science

Can someone check these?



Kendall (22lbs) starts from rest at the top of a 5.2 m tall slide

a. Find her speed at the bottom of the slide (height - 0.2m). Solve using conservation of energy

For this one I got 7.41 m/s

b. If she leaves like a horizontal projectile, how far (x) away from the edge of the slide will she land

For this one I got 11.2m

c. If you throw a softball straight up with a velocity of 8 m/s, how high will it go?

For this one I got 3.26m

d. How much sooner (sec) will a loud sound travel 1.54 km to you through steel (speed of sound in steel = 5950m/s) that in air? (speed of sound in air = 340 m/s)

For this one I got

steel: 3.86 sec
air: .22 sec

I got all the same answers except for D…
I would check over that answer as I got something way different. If you find a new answer post it and I will tell you if it is the same. I don't like to just post the answer I got because I believe that if the person sees the answer they (subconsciously) work to get that answer. I would rather you found the answer on your own or stay with the answer you got if mine turns out wrong :D.
(I will tell you that mine was a lot lower for steel and a little lower for air)

Just a tip, the sound would travel MUCH faster through the steel than it would through air.

You see:
Sound waves transfer better through denser materials, thus why sound moves around better in water than in air.

Light is the other way around
Light moves better through less dense objects, thus why light travels MUCH better in a vacuum then in actual atmosphere/air
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E: I saw you got an answer that pertains to what I just said after I read it again, my bad :p

I'll answer D only since Saint confirmed a - c.

Time(air) = 1540 m / 340 m/s
Time(steel) = 1540 m / 5950 m/s

Time(steel) - Time(Air) ~ 4.27 s