PHY 130: Exam 3
Consider two steel rods, A and B. B has three times the area and twice the length of A, so Young's modulus for B will be what factor times Young's modulus for A?
1.0
A hoop with mass, M, and radius, R, rolls along a level surface without slipping with a linear speed, v. What is the ratio of rotational to linear kinetic energy? (For a hoop, I = MR2.)
1/1
A cylinder with its mass concentrated toward the center has a moment of inertia of 0.2MR2. If this cylinder is rolling without slipping along a level surface with a linear speed v, what is the ratio of its rotational kinetic energy to its linear kinetic energy?
1/5
A non-uniform round object of mass M and radius R is found to have its total kinetic energy to be given by KE = Mv2 when rolling down an incline. What is this object's moment of inertia?
1/5
A solid sphere of radius R is placed on an incline that makes an angle θ with the horizontal. The sphere rolls down the incline without slipping. What is its acceleration?
5/7gsin(theta)
In a large tank of liquid, the hydrostatic pressure at a given depth is a function of
Choices a and c are both valid (depth and liquid density)
The Earth's density increases with depth. If instead the Earth had uniform density, but the same angular velocity and mass, how would its rotational kinetic energy compare to the actual value? a. It would be the same as the actual value.
It would be greater than the actual value
The quantity "angular momentum" (in terms of the fundamental quantities of mass, length, and time) is equivalent to:
ML2T−1
Three disks have the same mass and the same total kinetic energy. Disk #1 has radius R, disk #2 has radius 2R, and disk #3 has radius 3R. Which one has the highest v translational?
The all have the same v translational
Why do vapor bubbles get larger in boiling water as they approach the surface?
The pressure in the water decreases as the bubble moves toward the surface.
A hoop, solid sphere, and solid cylinder each have the same mass and same radius. When rolling down the same incline, which has the greatest torque from gravity on it?
They all have the same torque
The quantity "strain" expressed in terms of the fundamental quantities (mass, length, time) is equivalent to
a dimensionless quantity
A container is filled with water and the pressure at the container bottom is P. If the container is instead filled with oil having specific gravity 0.80, what new bottom pressure results?
a pressure < P
If a nonzero torque is applied to an object, that object will experience:
an angular acceleration
A U-tube is partially filled with water and then an immiscible liquid is added to the right side. The top of the liquid is a distance h1 above the level of interface between the liquid and water. On the left side of the tube the top of the water is a distance h2 above the liquid-water interface on the right side. What is the density of the liquid in terms of the
h2/h1
The fluid to which Bernoulli's equation is applied is based on what being conserved for the fluid?
its total mechanical energy
At a pressure of 1 atmosphere a column of mercury in a barometer is supported to the height h = 0.76 m. The density of mercury is 13.6 × 103 kg/m3. A barometer of similar design filled with water would support a column of water how high at a pressure of 1 atmosphere?
more than ten times h
A uniform solid sphere rolls down an incline of height 3 m after starting from rest. In order to calculate its speed at the bottom of the incline, one needs to know:
no more than is given in the problem
A pipe carrying water has a radius of 1.0 cm. If the flow velocity is 9.0 cm/s, which of the following characterizes the flow? Take the viscosity of water to be 1.0 × 10−3 N⋅s/m.
streamlined
A hoop, a solid sphere, and a solid cylinder each have the same mass, radius, and initial speed and are going up the same inclined plane. Which one goes the farthest?
the hoop
