Quiz theory Flashcards
The meter is the length of the path travelled by light in a vacuum during a time interval of 1/299 792 459 of a second
True
Vectors are a type of data that is characterized only by direction
False
When a particle has moved from position x1 to position x2 during a time interval t1 and t2 its average velocity during that interval depends on :
Displacement and duration of time interval
a force is a conservative force if:
the net work it does on a particle moving around any closed path, from an initial point and then back to that point, is zero
The frictional force is:
parallel to the surface and directed so as to opose the sliding
Instantaneous acceleration(or simply acceleration) a is the:
-the first time derivative of velocity v(t)
-the second time derivative of position x(t)
A normal force is the force on a body from a surface against which the body presses. The normal force is always perpendicular to the surface.
True
Kinetic frictional force exist only when object is at rest
False
Work W is energy transferred:
to or from an object via a force acting on the object
The number of Newton’s laws is
3
When we have a graph of an object’s acceleration a versus time t, we can integrate on the graph to find the velocity at any given time
True
When a cord is under tension, each end of the cord pulls on a body. The pull is:
Directed along the cord, away from the point of attachment to the body
Static frictional force exist only when object is at rest
True
The work on an object can be caused by force:
Only the component of that is along the displacement
Kinetic frictional force:
Is always in the direction opposite of the movement
