Distance and Displacement
A passenger in the rear seat of a car moving at a steady speed is at ________relative to the front seat of the car.
rest
Speed is the ratio of the distance an object moves to the amount of ________ needed to travel the distance.
time
An example that describes constant acceleration due only to a change in ________ is traveling around a circular track.
direction
An object that is ____________ may be slowing down, gaining speed, and changing direction.
accelerating
__________ nuclear force is associated with nuclear decay.
Weak
The distance of the width of a book can be most accurately measured with a ____________.
ruler
Instantaneous speed is measured at a particular ________.
instant
A speed-time graph shows that a car moves at 10 m/s for 10 s. The car's speed then steadily decreases until it comes to a stop at 30 s. The slope of the speed-time graph from 10 s to 30 s can be described as curved and __________.
upward
The kind of friction that occurs as a fish swims through water is __________ friction.
fluid
The weakest universal force is _______________.
gravitational
A person walks 1 mile every day for exercise, leaving her front porch at 9:00 am. and returning to her front porch at 9:25 am. The total displacement of her daily walk is___ miles.
0
A river current has a velocity of 5 km/h relative to the shore, and a boat moves in the same direction as the current at 5 km/h relative to the river. The velocity of the boat relative to the shore can be calculated by _________ the vectors.
adding
An open parachute increases __ ______ of a falling sky diver by increasing surface area.
air resistance
According to Newton's second law of motion, the acceleration of an object equals the net force acting on the object divided by the object's ___________.
mass
The SI unit of power is the _________.
watt
A ball is rolled uphill a distance of 5 meters before it slows, stops, and begins to roll back. The ball rolls downhill 9 meters before coming to rest against a tree. The magnitude of the ball's displacement is ___ meters.
4
The rate at which velocity changes is called ____________.
acceleration
The curved path followed by a ball being thrown forward is an example of ____________ motion.
projectile
Newton's_________law of motion describes action and reaction forces.
third
The power of a machine measures its rate of doing ____________.
work
Displacement vectors of 4 km south, 2 km north, 5 km south, and 5 km north combine to a total displacement of ___________ (# and direction)
2 km south
Objects in free fall near the surface ofthe Earth experience _____________ acceleration.
constant
An object moving at 30 m/s takes 5 s to come to a stop. The object's acceleration is__________.
–6 m/s²
The universal force that acts only on the protons and neutrons in a nucleus is ___________ nuclear.
strong
Work is a transfer of ___________.
energy