Answer:
42000N
Explanation:
First you calculate how much it would contract, and secondly you then calculate the force to stretch it by that amount.
1) linear thermal expansion coef brass 19e-6 /K
∆L = αL∆T = (19e-6)(1.85)(110) = 0.00387 meter or 3.87 mm
Second part involves linear elasticity.
for brass, young's modulus is 15e6 psi or 100 GPa
cross-sectional area of rod is π(0.008)² = 0.0002 m²
F = EA∆L/L
F = (100e9)(0.0002)(0.00387) / (1.85)
F = 42000 or 42 kN
The question is incomplete.
Here is the complete question (only part A):
Two children, Ferdinand and Isabella, are playing with
a water hose on a sunny summer day. Isabella is holding the hose
inher hand 1.0 meters above the ground and is trying to
spray Ferdinand, who is standing 10.0 meters away.
Part A
Will Isabella be able to spray Ferdinand
if the water is flowing out of the hose at a constant
speed Vo of 3.5
meters per second? Assume that the hose is pointed parallel to the
ground and take the magnitude of the acceleration due to gravity
to be 9.81 meters per second, per second.
Answer: No. Since the water jet runs 1.58 m before falling into the ground, it cannot spray Ferdinand who is 10.0 m away.
Explanation:
1) Data:
yo = 1.0m
Vox = 3.5 m/s
Voy = 0
x = 10.0 m
g = 9.81 m/s²
2) Type of motion and formulas
Parabolic motion
y = yo + Voy×t - g×t² / 2
x = Vox × t
3) Solution:
i) From y = yo + Voy×t - g×t² / 2 calculate t until the water reaches the ground (y = 0).
From the data yo = 1, and Voy = 0
0 = 1.0 - 4.905t² ⇒ t = √ (1.0 / 4.905) = 0.45 s
ii) Calculate x using t = 0.45s
From the data Vox = 3.5m/s
x = Vox × t = 3.5m/s × 0.45s = 1.58 m
iii) Conclusion: since the water jet runs 1.58 m before falling into the ground, it cannot spray Ferdinand who is 10.0 m away.
Straight line with positive slope equals 9.8 (or 10)
O2 refers to two oxygen atoms bonded together, while 2 O refers to two oxygen atoms that are not bonded to each other. They both have two oxygen atoms, but in O2, the oxygen atoms are bonded, while in 2O, the atoms are not.
Answer:
-0.53 m/s²
Explanation:
Acceleration is the change in velocity over change in time.
a = Δv / Δt
First, convert m/min to m/s.
80 m/min × (1 min / 60 s) = 1.33 m/s
a = (0 m/s − 1.33 m/s) / 2.5 s
a = -0.53 m/s²