Answer:
(a) Vf = 128 ft/s
(b) K.E = 122.8 Btu
Explanation:
(a)
In order to find the velocity of the object just before striking the surface of earth or the final velocity, we use 3rd equation of motion:
2gh = Vf² - Vi²
where,
g = 32.2 ft/s²
h = height = 253 ft
Vf = Final Velocity = ?
Vi = Initial Velocity = 10 ft/s
Therefore,
(2)(32.2 ft/s²)(253 ft) = Vf² - (10 ft/s)²
16293.2 ft²/s² + 100 ft²/s² = Vf²
Vf = √(16393.2 ft²/s²)
<u>Vf = 128 ft/s</u>
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(b)
The kinetic energy of the object before it hits the surface of earth is given by:
K.E = (0.5)(m)(Vf)²
where,
m = mass of object = 375 lb
K.E = Kinetic energy of object before it strikes the surface of earth = ?
Therefore,
K.E = (0.5)(375 lb)(128 ft/s)²
K.E = 3073725 lb.ft²/s²
Now, converting this to Btu:
K.E = (3073725 lb.ft²/s²)(1 Btu/25037 lb.ft²/s²)
<u>K.E = 122.8 Btu</u>
Chattanooga - Chatype, London - Johnston, Berlin - BMF Change, Milan - Milano City, Eindhoven - Eindhoven, Stockholm - Stockholm Type, Minneapolis, and St. Paul - Twin.
Answer:
Explanation:
Given
Volume of fixed chamber 
Initial Temperature 
Final Temperature 
Heat Supplied 
From First law of thermodynamics
Change in internal energy of the system is equal to heat added minus work done by the system
as the volume is fixed therefore work
thus 
for mono-atomic gas is 
and 1 mole contains 
thus No of molecules
No of molecules
Answer:
2.4 m/s". 1
Explanation:
A jet with mass m = 8 x 10* kg jet accelerates down the runway for takeoff at 2.4 m/s". 1
Answer:
Volume of secret cavity = 4 x 10⁻⁶m³
Explanation:
The weight of the sculpture in air is 15.76 N
Mass of the sculpture = 1.61 kg
Mass = Volume x Density
1.61 = V x 8470
Volume of brass =1.90 x 10⁻⁴ m³
When it is submerged in water, the weight is 13.86 N.
That is
Weight of sculpture - Weight of water displaced = 13.86 N
15.76 - Weight of water displaced = 13.86
Weight of water displaced = 1.9 N
Mass of water displaced = 0.194 kg
Mass = Volume x Density
0.194 = V x 1000
Volume of water displaced =1.94 x 10⁻⁴ m³
Volume of secret cavity = Volume of water displaced - Volume of brass material
Volume of secret cavity = 1.94 x 10⁻⁴-1.94 x 10⁻⁴ = 0.04x 10⁻⁴ = 4 x 10⁻⁶m³
