Physics Final
A pipe with a diameter of 2-in tapers down to a 1-in diameter pipe and has an incompressible fluid flowing in it. Which of the following statements is correct?
(All of the Above) - pressure in the 2-in pipe is greater than in the 1-in pipe - Velocity of fluid in the 1-in pipe is greater than in the 2-in pipe. - The volume of fluid flowing per unit time is the same in both pipes.
Which of the following statements concerning speed is/are correct?
(None of the above) - speed must change in order to have an acceleration - constant speed implies a constant acceleration - speed is a vector
An apple falls from a tree. It hits the ground at a speed of 5 m/s. What is the fall time?
0.5 s
Jane pushes a box 4 m along a horizontal surface by applying a 25 N horizontal force. What work does she do?
100 J
Object 1 has three times the specific heat capacity and four times the mass of Object 2. the two objects are given the same amount of heat. If the temperature of Object 1 changes by an amount deltaT, the change in temperature of Object 2 will be...
12deltaT
A bicycle has wheel that are 60 cm in diameter. What is the angular speed of these wheel when it is moving at 4 m/s?
13 rad/s
What is the frequency of the fundamental mode of vibration of a steel piano wire stretched to a tension of 440 N? The wire is 0.6 m long and has a mass of 5.6 g.
181 Hz - solve using f = (1/2L) x SQRT (T/(m/L)) - f = (1/2x 0.6) x SQRT (440/ (5.6x10^-3/0.6))
A violin string of length L is fixed at both ends. Which one of the following in NOT a wavelength of a standing wave on the string?
2L
How much work must be done by frictional forces in slowing a 1000-kg car from 26.1 m/s to rest?
3.41 x 10^5 J - solve using W = Fd or W = m*a*d - W = 0.5 (26.1)^2 (1000)
Water flowing through a cylindrical pipe suddenly comes to a section of pipe where the diameter decreases to 86% of its previous value. If the speed of the water in the larger section of the pip was 32 m/s what is its speed in this smaller section if the water behaves like an ideal incompressible fluid?
37 m/s - solve using A1V1 = A2V2 - 1 x 32 = 0.86 x V2 - solve for V2
A tiger is running in a straight line. If we double both the mass and speed of the tiger, the magnitude of its momentum will increase by what factor?
4
The melting point of aluminum is 660 degrees C, its latent heat of fusion is 4.00 x 10^5 J/kg, and its specific heat is 900 J/kg*K. How much heat must be added to 500 g of aluminum originally at 27 degrees C to completely melt it?
485 kJ - solve using Q = m*c*deltaT + m* - Q = 0.5 (900 (660-27) +4 * 10^5)
A 1200-kg car is pulling a 500-kg tailer along level ground. Friction of the road on the trailer is negligible. The car accelerates with an acceleration of 1.3 m/s^2. What is the force exerted by the car on the trailer?
650 N - solve using F = ma - f = 500 x 1.3
A force of 17 N is applied to the end of a 0.63-m long torque wrench at an angle of 45 degrees from a line joining the pivot point to the handle. What is the magnitude of the torque about the pivot point produced by this force?
7.6 N*m - solve using T = Fd cos (theta) - T = (17) (0.63) cos (45)
A 75-N box rests on a perfectly smooth (frictionless) horizontal surface. The minimum force needed to start moving the box is
75 N
A 3 kg object is initially at rest. It receives an impulse of magnitude 15 Ns. After the impulse, the object has:
A momentum of magnitude 15 kg/s
"At any two points along the same streamline in a non viscous, incompressible fluid in a steady flow, the sum of the pressure, the kinetic energy per unit volume, and the potential energy per unit volume has the same value." This is a statement of:
Bernoulli's Law
Two balls, identical except for color, are projected horizontally from the roof of a tall building at the same instant. The initial speed of the red ball is twice the initial speed of the blue ball. Ignore air resistance
Both balls land at the same instant with different speeds
A satellite is in orbit around the Earth. Which one feels the greater force?
Earth and the satellite feel exactly the same force
A spider sits on a turntable rotating at a constant 33 rpm. The acceleration of the spider is:
Greater the farther the spider is from the central axis
A spinning ice skater on extremely smooth ice is able to control the rate at which she rotates by pulling in her arms. Which of the following statements are true about the skater during this process?
Her angular momentum remains constant
The intensity of a spherical wave from a point source at a distance d from the source is I. What is the intensity at a distance 2d from the source?
I/4
In the Ideal Gas Law, what scale is used for the temperature?
Kelvin
Two men, Joel and Jerry, push against a car that has stalled, trying unsuccessfully to get it moving. Jerry stops after 10 min, while Joel is able to push for 5 min longer. Compare the work they do on the car.
Neither of them does any work
Complete the following statement: The transfer of heat by convection will occur
Only in the presence of a liquid or a gas
The specific heat capacity of iron is approximately half that of aluminum. Two balls of equal mass, one made of iron and the other of aluminum, both at 80 degrees C, are dropped into a thermally insulated jar that contains an equal mass of water at 20 degrees C. Thermal equilibrium is eventually reached. Which one of the following statements concerning the final temperatures is true?
The aluminum ball will reach a higher final temperature than the iron ball.
When an object is in translation equilibrium, which of the following is NOT true?
The object has a constant velocity
An object moves in a circular path at a constant speed. compare the direction of the object's velocity and acceleration vectors.
The vectors are perpendicular to each other.
The total energy of a simple harmonic oscillating system is
a non-zero constant
The second law of thermodynamics leads us to conclude that
disorder in the universe is increasing with the passage of time
A simple harmonic oscillator oscillates with frequency f when its amplitude is A. If the amplitude is now double to 2A, what is the new frequency?
f
A steel ball sinks in water but floats in a pool of mercury, which is much denser than water. Where is the buoyant force on the ball greater?
floating on the mercury
A hypothetical planet has a mass of one-half that of the Earth and a radius of twice that of the Earth. What is the acceleration due to gravity on the surface of the planet in terms of g, the acceleration due to gravity at the surface of the Earth?
g/8
What is the wavelength of the wave shown in the figure? (no specific numbers on x or y axis)
it cannot be determined from the given information
You slam on the brakes of your car in a panic, and skid a certain distance on a straight level road. If you had been traveling twice as fast, what distance would the car have skidded under the same conditions?
it would have sided 4 times farther
A mass on a spring undergoes simple harmonic motion. When the mass is at its maximum distance from the equilibrium position, which of the following statements is true?
its speed is zero.
Grandfather clocks are designed so they can be adjusted by moving the bob at the bottom of the pendulum up or down. Suppose you have a grandfather clock at home that runs fast. Which adjustments of the bob would make it more accurate?
lower the bob
A rock attached to a string, swings counter-clockwise in a horizontal circle. The string breaks at point P in the figure. Which path will the rock follow?
path perpendicular to the circle
You are in a train traveling on a horizontal track and notice that a piece of luggage state to slide directly toward the front of the train. From this observation, you can conclude that this train is
slowing down
When you blow some air above a paper strip, the paper rises. This happens because
the air above the paper moves faster and the pressure in lower.
The two dams are identical with the exception that the water reservoir behind dam A extends twice the horizontal distance behind it as that of dam B. The depth of water is the same in both reservoirs. Which of the following regarding these dams is correct?
the horizontal distance of the water behind the two dams does not determine the force on them
As shown in the figure, fluid fill a container having several sections. At which of the indicated points is the pressure greatest? (all points are on the same point on the y axis)
the pressure is the same at each of the labeled points
A rocket explodes into two fragments, one 25 times heavier than the other. The magnitude of the momentum change of the lighter fragment is
the same as the momentum change of the heavier fragment
A train passes you standing by the track blowing its whistle. You note that:
the wavelength went from shorter to longer
On a cold day, a piece of metal feels much colder to the touch than a piece of wood. This is due to the difference in which one of the following physical properties of these materials?
thermal conductivity
When is the average velocity of an object equal to the instantaneous velocity?
when the velocity is constant.
