PHY 221–001
OaktonCommunity College
Spring 2012
Practice Test 4
Useful formulas:
Fspring = –kx
K1 + Ugrav, 1 + Uelastic, 1 + Wother = K2 + Ugrav, 2 + Uelastic, 2
Simple harmonic motion:
x(t) = Acos(t + )
vx,max = A
Angular SHM: = cos(t + )Simple pendulum:
Physical pendulum:
Damped oscillation:
Underdamped: where:
Critically damped: Overdamped: where s1, s2 < 0
pabs = pgauge + patm
PHY 221–001
OaktonCommunity College
Spring 2012
Practice Test 4
Q = mcT = nCTQ = mLHnet = Ae (T4 – Ts4)
Ideal gases: pV = nRTpV = NkT
Monatomic gas: Diatomic gas: Monatomic solid: CV = 3R
ETH = Q + WdE = nCVdTCp = CV + R
Adiabatic process, ideal gas:
TK = TC + 273.151 cal = 4.186 J1 Btu = 1055 J
Water:Lf = 3.34 × 105 J/kgLv = 2.256 × 106 J/kg
NA = 6.022 × 1023 molecules/mol
Conversion factors:100 cm = 1 m1 km = 1000 m1 m = 109 nm1 g/cm3 = 1000 kg/m3
1 m3 = 1000 L = 106 cm31 Pa = 1 N/m2
1 atm = 1.013×105 Pa = 1.013 bar = 14.70 lb/in21 psia = 1 lb/in2 absolute1 psig = 1 lb/in2 gauge
PHY 221–001
OaktonCommunity College
Spring 2012
Practice Test 4
1) A block of mass 0.500 kg is attached to springs on a frictionless horizontal track. When the block is held at a position 0.100 m away from the equilibrium position, the force of the springs is measured to be 1.25 N. When the block is set in simple harmonic motion, what will be the period of the motion?
2) For the block-spring system of problem 1, if the maximum displacement is 0.100m, then what is the maximum amount of kinetic energy the block has during its motion?
PHY 221–001
OaktonCommunity College
Spring 2012
Practice Test 4
3) If you wanted to make a simple pendulum that had a period of 2.00s, how long would it be?
4) Given that atmospheric pressure is 1.013 × 105 Pa, and that the density of sea water is 1.03 × 103 kg/m, what is the absolute pressure at a depth of 5.00 m beneath the surface of the sea?
PHY 221–001
OaktonCommunity College
Spring 2012
Practice Test 4
5) Sea water has a density of sw = 1.03 × 103 kg/m3, and lead has a density of Pb = 1.14 × 104 kg/m3. While lifting a large lead block that is submerged under sea water, a force of 8915 N is used. What is the mass of the lead block?
6) Water comes into a house through a pipe of diameter d = 2.00 cm at a pressure of 44.1 psig. A 1.00cm diameter pipe takes the water to a bathroom 5.00 m above. If the only water flow is through a faucet in the bathroom, and the incoming flow rate is 0.471L/s: a) What is the flow rate out of the bathroom faucet? b)What is the gauge pressure of the water coming out of the faucet?
PHY 221–001
OaktonCommunity College
Spring 2012
Practice Test 4
7) A constant-volume container has a volume of 22.4 L (0.0224 m3), and it contains an ideal gas whose pressure is atmospheric pressure (1.013×105 Pa), and whose temperature is 0°C. a) How many moles of molecules are in the container b) What is the pressure of the gas after the temperature is raised to 10°C?
8) A 100.0 g sample of ice starts at a temperature of –5.0 °C, and is placed in a beaker containing 1,000.0g of water at 50.0°C. Assuming that no heat leaves the water-ice system, what is the final temperature of the water after the ice melts? The specific heat of ice is 2090 J/kg∙K, and the specific heat for water is
4186 J/kg∙K.
PHY 221–001
OaktonCommunity College
Spring 2012
Practice Test 4
9) Two objects are connected to each other in 5 different places with copper bars, each of which is 10.0cm long with a cross-sectional area of 4.00cm2. The temperatures of the two objects are held at 100°C and 0°C, respectively. What is the total heat current, in watts, between the two objects? Ignore heat loss from the bars to the air. (kCu = 385.0 W/m∙K)
10) The temperature of the sun is 5800 K, and its radius is 6.96×108m. If the temperature of its surroundings is 2.7 K, and its emissivity is e = 1.00, what heat current is the sun radiating?
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