978

Physics Heat & Thermodynamics Level: High School

The dew point temperature of a saturated air parcel that is rising will:

a. Decrease.

b. Increase.

c. Decrease and then increase.

d. Increase and then decrease.

e. Remain the same.

Decrease.



977

Physics Heat & Thermodynamics Level: High School

Saturation of an air parcel occurs when it has :

a. 100% relative humidity.

b. 100% by volume of water vapor.

c. A temperature above dew point temperature.

d. A temperature equals to dew point temperature.

e. Both a and d.

f. None of the above.

e. Both a and d.



976

Physics Heat & Thermodynamics Level: High School

A system for which the change in entropy of one part of the system is negative is a -------- process .

a. Unnatural.

b. Natural .

c. Reversible.

d. Irreversible.

e. Insufficient data.

c. Reversible.



975

Physics Heat & Thermodynamics Level: High School

Three moles of an ideal gas are contained in a 30m^3 vessel at a pressure of 3.50 x 10^5 N/m^2 . The temperature of the gas is :

a. 1.26 x 10^5 K

b. 4.21 x 10^4 K

c. 833 K

d. 4.17 x 10^-1 K

e. 2.52 x 10^5 K




974

Physics Heat & Thermodynamics Level: High School

An ideal gas undergoes an adiabatic compression . If its original volume and temperature were 0.5 m^3 and 373 K, What is its final temperature if its final volume is 1.0 m^3 ?

a. 63 K

b. 186 K

c. 235 K

d. 373 K

e. 273 K




973

Physics Heat & Thermodynamics Level: High School

The efficiency of any heat engine :

a. equals that of a carnot engine with the same intake and exhaust temperature .

b. equals W/Qinput .

c. depends only on its intake temperature .

d. depends only on it exhaust temperature .

e. equals that of a reversible heat engine with the same intake and exhasust temperature .

b. equals W/Qinput .



972

Physics Heat & Thermodynamics Level: High School

In order to apply the first Law of Thermodynamics in a situation, which of the following must be true ?

a. The process must be irreversible

b. The system must be in thermodynamic equilibrium throughout the entire process.

c. The system need only be in thermodynamic equilibrium in its final and initial states.

d. The process must be adiabatic or at least partially so.

e. The process must be isentropic.

c. The system need only be in thermodynamic equilibrium in its final and initial states .



971

Physics Properties Of Matter Level: High School

A hunting knife weighing 2-Newtons and occupying a volume of 2.5 x 10^-4 m^3 is accidentally dropped in a lake . Which statement is true ?

a. The buoyant for is 0.45 Newton .

b. The knife will sink to the bottom and stay there .

c. Both a and b are true .

d. The knife will float .

e. Insufficient data .




970

Physics Properties Of Matter Level: High School

Archemedes Principle

A block of unknown density is hung from a spring scale. The scale reads 2 Newtons. Then a beaker of water is brought up under the block. The block floats on the water. Which of the following is true statements ?

a. The density of the block is greater than the density of water.

b. The scale will read slightly less than 2 Newtons but more than 1 Newton.

c. The buoyant force of the water is 2 Newtons.

d. The scale will read zero Newtons.

e. Both c and d are true.

f. Both a and c are true.

g. None of the above.

e. Both c and d are true .




969

Physics Properties Of Matter Level: High School

A man is swimming 2-meters below the surface of a pool . The pool is 6 meters deep. What is the pressure the man experiences ? Assume the pool is at sea level.

a. 1.96 x 10^4 N/m^2

b. 1.40 x 10^5 N/m^2

c. 1.39 x 10^4 N/m^2

d. 1.21 x 10^5 N/m^2




968

Physics Gravitation Level: High School

On a planet with an atmospheric scale height of one kilometer and a seal level pressure of 2 x 10^6 N/m^2 , Which of the following is true ?

a. The top of the atmosphere is at 1 km

b. Pressure decreases by one-half for every kilometer of altitude increase above 1 –km

c. Sea level is at 1 -km

d. The atmospheric pressure at 0.5 km above the surface is 1.21 x 10^6 N/m^2

e. The atmospheric pressure at 0.5 km above the surface is 3.30 x 10^6 N/m^2




967

Physics Work,Power & Energy Level: High School

A uniform sphere of mass 2-kg and radius 1.0 meters is accelerated from rest. The final velocity of the center of mass is 3.0 m/s , and the final angular velocity of the sphere is 2 radians/sec . What is the total work done on the sphere ? Assume the sphere is solid .

a. 9 J

b. 10.6 J

c. 1.6 J

d. 7.4 J

e. 0 J




966

Physics Work,Power & Energy Level: High School

A man raises a 60-kg sack a distance of 1.5 meters to his shoulder , carries it for a distance of 300 meters along a level road and then lowers it to the ground . How much total work does gravity do ?

a. 883 J

b. 0 J

c. -883 J

d. 90 J

e. -90 J

b. 0 J



965

Physics Kinematics Level: High School

If the velocity of a body increases , we may be sure that during the period of this increase :

a. The distance of the body from the origin decreases.

b. The distance of the body from the origin increases.

c. The acceleration of the body increases .

d. The acceleration of the body remains constant .

e. The body accelerates .

e. The body accelerates .



964

Physics Kinematics Level: High School

An artillery shell has been launched at a 45 degree angle. If air friction is neglected , the maximum acceleration occurs :

a. Just after leaving the gun .

b. At the shell’s maximum height .

c. Just before hitting the ground .

d. Acceleration is constant through out its flight .

e. At 0.707 of the shell’s maximum height .

d. Acceleration is constant through out its flight .

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