Final Exam Flashcards
Kinetics is the study of:
a. Geometric aspect of the motion
b. analysis of forces that causes the motion
c. Both of the above
d. None of the above
a. Geometric aspect of the motion
If you model a body using a particle, it can:
a. Translate
b. rotate
c. Have no mass
d. Moments can be applied
a. Translate
A rigid body can:
a. Rotate
b. Translate
c. Have mass and moments can be applied
d. All of the above
d. All of the above
Choose the correct options:
a. Distance is a positive scalar
b. Displacement is a vector quantity and can be negative and zero
c. Distance can be negative
d. Acceleration will always point in the direction in which the body is moving
a. Distance is a positive scalar
b. Displacement is a vector quantity and can be negative and zero
Which statement is incorrect?
a. Velocity is defined as rate of change in the position
b. Acceleration is defined as rate of change in the velocity
c. Displacement is defined as change in the position
d. Position of particle cannot be negative
d. Position of particle cannot be negative
A particle has an initial velocity of 3 m/s to the left. If it then passes through the ‘same location’ 5 seconds later with a velocity of 5 m/s to the right, what is the average velocity of the particle during this 5 second time interval?
a. 10 m/s towards the right
b. 40 m/s towards the right
c. 4 m/s towards the right
d. 0 m/s
d. 0 m/s
The slope of the velocity time graph gives:
a. Distance
b. Displacement
c. Acceleration
d. None of the above
c. Acceleration
If the position of a particle has a quadratic (degree of 2) relation with time, then the particle is moving with:
a. constant velocity
b. constant acceleration
c. increasing acceleration
d. deceleration
b. constant acceleration
The mathematical relation that describes an acceleration time graph is given by a linear polynomial function. What will be the degree of polynomial function that will describe the position of the particle?
a. 1
b. 2
c. 3
d. 4
c. 3
Area under the acceleration time graph gives:
a. Change in velocity
b. position
c. displacement
d. None of the above
a. Change in velocity
The velocity vector is always:
a. tangent to the path
b. tangent to the hodograph
c. parallel to hodograph
d. None of the above
a. tangent to the path
The acceleration vector is always:
a. tangent to the path
b. tangent to the hodograph
c. All of the above
d. None of the above
b. tangent to the hodograph
A baseball player hits a ball into a projectile motion. Which of the following statements best describes the motion of the ball after it is thrown?
a. Its vertical speed remains the same, and its horizontal speed increases
b. both vertical and horizontal speed remains the same
c. both vertical and horizontal speed changes
d. its vertical speed changes, and its horizontal speed remains the same
d. its vertical speed changes, and its horizontal speed remains the same
A cannonball is fired and follows the parabolic path shown below. Air resistance is negligible. Which of the following best describes the direction of the acceleration of the ball at point C?
a. Down
b. Left
c. Right
d. Up
a. Down
A projectile is fired with an initial velocity at an angle with the horizontal. Which of the following graphs describes the direction of velocity and acceleration in the horizontal direction?
Constant velocity & zero acceleration
If a particle moves along a curve with a constant speed, then its tangential component of acceleration is:
a. Positive
b. Negative
c. Zero
d. Constant
c. Zero
The normal component of acceleration represents:
a. the time rate of change in the magnitude of the velocity
b. the time rate of change in the direction of the velocity
c. magnitude of the velocity
d. direction of the total acceleration
b. the time rate of change in the direction of the velocity
A particle traveling in a circular path of radius 300 m has an instantaneous velocity of 30 m/s and its velocity is increasing at a constant rate of4 m/s^2. What is the magnitude of its total acceleration at this instant?
a. 3m/s^2
b. 4m/s^2
c. 5m/s^2
d. -5m/s^2
c. 5m/s^2
The radial component of the velocity vector is the measure of:
a. Rate of increase or decrease in the length of the radial coordinate
b. Rate of motion along the circumference of a circle of radius r
c. All of the above
d. None of the above
a. Rate of increase or decrease in the length of the radial coordinate
Which of the statements if true:
a. Unit of angular velocity is rad/s
b. Unit of angular acceleration is rad/s^2
c. The unit vectors in polar coordinates do not change its direction with time (and the axis remain fixed)
d. In planar (2D) motion we use polar coordinates, while in 3D motion we use cylindrical coordinates
a. Unit of angular velocity is rad/s
b. Unit of angular acceleration is rad/s^2
d. In planar (2D) motion we use polar coordinates, while in 3D motion we use cylindrical coordinates
What is the polar coordinate for a point which has a rectangular coordinate of (3,4)?
a. (5, 0.927)
b. (4, 0.927)
c. (5, 0.1)
d. (5, 5)
a. (5, 0.927)
The velocity of B relative to A is defined as:
a. Vb-Va
b. Va-Vb
c. Vb+Va
d. Va+Vb
a. Vb-Va
Determine the velocity of plane A with respect to plane B.
a. (400i + 520j) km/hr
b. (1220i - 300j) km/hr
c. (-181i - 300j) km/hr
d. (-1220i + 300j) km/hr
b. (1220i - 300j) km/hr
Newton’s second law can be written in mathematical form as F=ma. Within the summation of forces, F, _______ are(is) not included.
a. external forces
b. weight
c. internal forces
d. All of the above
c. internal forces
In dynamics, the friction force acting on a moving object is always:
a. in the direction of its motion
b. a kinetic friction
c. a static friction
d. zero
b. a kinetic friction
The block (mass = m) is moving upward with a speed v. Draw the FBD if the kinetic friction coefficient is uk
b. weight straight down, normal perpendicular to surface, friction down slope
The positive n direction of the normal and tangential coordinates is:
a. normal to the tangential component
b. always directed toward the center of curvature
c. normal to the bi-normal component
d. All of the above
d. All of the above
The “normal” component of the equation of motion is written as Fn=man, wher Fn is referred to as the:
a. impulse
b. centripetal force
c. tangential force
d. inertia force
b. centripetal force
When the forces acting on a particle are resolved into cylindrical components, friction forces always act in the _______ direction.
a. radial
b. tangential
c. transverse
d. none of the above
b. tangential
The normal force which the path exerts on a particle is always perpendicular to the:
a. radial line
b. transverse direction
c. tangent to the path
d. None of the above
c. tangent to the path
What is the work done by the force F? (displacement to the right, force straight up)
a. Fs
b. -Fs
c. Zero
d. None of the above
c. Zero
Which of the following statements are correct?
a. Work is a scalar quantity
b. Work of a weight is independent of path
c. A force perpendicular to the displacement of the particle can do work on the particle
d. Work done by friction on a body sliding down an inclined plane is negative work
a. Work is a scalar quantity
b. Work of a weight is independent of path
d. Work done by friction on a body sliding down an inclined plane is negative work
In case of negative work, the angle between the force and displacement can be:
a. 0 degrees
b. 45 degrees
c. 90 degrees
d. 160 degrees
d. 160 degrees
A ball is thrown upward. The work done by the weight on the ball at this instant is:
a. positive
b. negative
c. zero
d. None of the above
b. negative
A car is accelerated on a levelled road and attains a speed of 4 times its initial speed. In this process, kinetic energy of the car:
a. does not change
b. becomes 4 times that of the initial kinetic energy
c. becomes 8 times that of the initial kinetic energy
d. becomes 16 times that of the initial kinetic energy
d. becomes 16 times that of the initial kinetic energ
The formula definition of power is:
a. dU/dt
b. Fv
c. Fdr/dt
d. all of the above
d. all of the above
The power supplied by a machine will always be ______ the power supplied to the machine.
a. less than
b. equal to
c. greater than
d. A or B
a. less than
A car is traveling a level road at 25 m/s. The power being supplied to the wheels is 80000 W. Find the combined friction force on the tires.
a. 863 N
b. 2500 N
c. 3200 N
d. 2.0*10^6 N
c. 3200 N
Choose the correct statements:
a. Weight is a conservative force
b. Conservation of energy can be applied for problems where work done by friction is involved
c. Spring force is a non conservative force
d. Friction is a non conservative force
a. Weight is a conservative force
d. Friction is a non conservative force
The potential energy of a spring is ________.
a. always negative
b. always positive
c. positive or negative
d. equal to ks
b. always positive
When the potential energy of a conservative system increases, the kinetic energy ________.
a. always decreases
b. always increases
c. could decrease or increase
d. does not change
a. always decreases
The linear impulse and momentum equation is obtained by integrating the _____ with respect to time.
a. friction force
b. equation of motion
c. kinetic energy
d. potential energy
b. equation of motion
Which parameter is not involved in the linear impulse and momentum equation?
a. velocity
b. displacement
c. time
d. Force
b. displacement
Calculate the impulse due to the force:
a. 20 kgm/s
b. 10 kgm/s
c. 5 Ns
d. 15 Ns
b. 10 kg*m/s (area of triangle)
Jet engines on the 100 Mg VTOL aircraft exert a constant vertical force of 981 kN as it hovers. Determine the net impulse on the aircraft over t = 10 seconds.
a. -981 kNs
b. 0 kNs
c. 981 kNs
d. 9810 kNs
b. 0 kN*s
If a rigid body is in translation only, the velocity at points A and B on the rigid body ______.
a. are usually different
b. are always the same
c. depend on their position
d. depend on their relative position
b. are always the same
A frisbee is thrown and curves to the right. It is experiencing:
a. rectilinear translation
b. curvilinear translation
c. pure rotation
d. general plane motion
d. general plane motion
There are two gears A and B that are in contact and moving as shown in figure. Find the angular speed of gear B at this instant. Wa = 20 rad/s, Ra = 0.2 m, Rb = 0.4 m.
a. 1 rad/s
b. 5 rad/s
c. 4 rad/s
d. 10 rad/s
d. 10 rad/s
