A-01: Elementary Mechanics And Dynamics Flashcards
A bar is pivoted on the left end and a force is applied upwards on the right end. The rotation of the bar will be:
A. Clockwise
B. Counter-clockwise
C. Downward
D. Upward
B. Counter-clockwise
Static friction is:
A. Always less than kinetic friction
B. The force required to keep an object moving
C. Less than the force required to keep an object moving at a constant speed
D. Always greater than kinetic friction
D. Always greater than kinetic friction
Displacement is:
A. A vector quantity
B. A scalar quantity
C. Measured by the actual path the object travels
D. How far an object has moved
A. A vector quantity
In the case of static friction, if the downward force between the surfaces is doubled, then the friction will:
A. Decrease by half
B. Remain constant
C. Double
D. The square root of the downward force
C. Double
Which of the following is an example of a static body ?
A. A body colliding with another body and deflecting in a new direction
B. A body that is decelerating
C. A rigid body that is at rest
D. A body moving at uniform velocity along a straight line
C. A rigid body that is at rest
Speed of an object in a given direction
A. Speed - direction
B. Speed + direction
C. Speed x velocity
D. Speed divided velocity
D. Speed divided velocity
The capacity of a body to do work is defined as:
A. Energy
B. Power
C. Pressure
D. Force
A. Energy
Which ratio determines the efficiency of a machine?
A. The output work (divided) by the input work
B. (Load x distance moved by load) x (effort x distance moved by effort)
C. (Effort x distance moved by effort) divided by (load x distance moved by load)
D. The input work divided by the output work
A. The output work divided by the input work
To start a body moving which of the following must be overcome?
A. Kinetic friction
B. Static friction
C. Fluid friction
D. Rolling friction
B. Static friction
When a body falls from a height, what is its potential energy converted to?
A. Watts
B. Friction
C. Kinetic energy
D. Power
C. Kinetic energy
In simple machines, “velocity ratio” is defined as :
A. The reaction at the fulcrum to balance the net forces on the system
B. The ratio of the load to the effort
C. The ratio of the distance moved by the effort to the distance moved by the load
D. The ratio of the work output to the work input
C. The ratio of the distance moved by the effort to the distance moved by the load
The ratio of the load to the effort in a simple machine is called the:
A. Velocity ratio
B. Actual mechanical advantage
C. Efficiency
D. Power
B. Actual mechanical advantage
The rate of doing work is called the ____
A. Power
B. Kinetic energy
C. Potential energy
D. Work
A. Power
How is acceleration defined ?
A. Velocity divided by acceleration
B. Change of velocity divided by time taken to change
C. Acceleration divided by velocity
D. Time taken to change divided by velocity
B. Change of velocity divided by time taken to change
