Part (a)
Let h = depth of water surface from the top of the well, m
Because the stone is dropped, its initial velocity is zero.
Let t₁ = time for the stone to drop, s
Then
h = (1/2)*(9.8 m/s²)*(t₁ s)²
t₁ = √(h/4.9) s = 0.4518√h s
The velocity of sound is 336 m/s.
The time for the sound wave to travel from the water surface to the top of the well is
t₂ = h/336 m/s
Because the time before the sound is heard is 2.4 s, therefore
t₁ + t₂ = 2.4
0.45181√h + h/336 = 2.4
Multiply through by 336.
151.8082√h + h = 806.4
h - 806.4 = -151.8082√h
h² - 1612.8h + 6.5028 x 10⁵ = 2.3046 x 10⁴h
h² - 2.4659 x 10⁴h + 6.5028 x 10⁵ = 0
Solve with the quadratic formula.
h = 0.5[2.4659 x 10⁴ +/- 2.4606 x 10⁴]
= 24632 m or 26.5 m
Test the two answers.
When h = 24632,
t₁ = 0.4518√(24632) = 70.9 s (Not acceptable)
When h = 26.5 m,
t₁ = 0.4518√(26.5) = 2.3258 s, t₂ = 26.5/336 = 0.0789 s,
t₁+t₂ = 2.4 s (CORRECT)
Answer: h = 26.5 m
Part (b)
If travel time for the sound is ignored, then
0.4518√h = 2.4
h = (2.4/0.45118)² = 28.2 m
The percent error is 100*[(28.2 - 26.5)/26.5] = 6.42%
Answer: The error is 6.4%
Answer:
140 beats per minute
Explanation:
There are 60 seconds in a minute and we know that Sherry felt 14 beats in 6 seconds if you multiply 6 by 10 you get 60 seconds which can be 1 minute. Then you multiply 14 by 10 since you 14 by 10 since you multiplied 6 by 10 and you get 140 beats per minute.
Answer:
Explanation:
Momentum conservation

Kinetic energy conservation

Solve the system
Answer:
8.505 m
Explanation:
Let V1 and V2 be velocities of puck A and B respectively
Since A and B move in the same direction, so the relative velocity will be V1+V2=3.5+3.9=7.4m/s
Or
Vr=7.4 m/s
Distance=S= 18 m
Time =t=?
S=Vr×t
==> t=S/Vr
==> t= 18/7.4=2.43 sec
At this time both will strike together
<em><u>Distance by puck A</u></em>
<em>V1=3.5 m/s</em>
Time=t= 2.43 sec
Distance covered=d=?
d=V1×t=3.5×2.43=8.505 m
So, puck A will cover 8.505 meters before collision
Explanation:
Yes, it takes more energy to vaporize 1 kg of saturated liquid water at than it would at .