Exam Review: Chapter 3 Practice Test

What is the acceleration of a car that maintains a constant velocity of 100 km/hr for 10 seconds? a) 0 b) 10 km/hr/s c) 10 m/s/s d) 100 km/hr/s e) 0.1 km/hr/s

a (constant velocity = no acceleration: this is bc acceleration is the rate at which velocity changes)

Motion that you can feel is called ______

acceleration

The change in an object's velocity in a certain amount of time is called the object's ______

acceleration

______ is the kind of motion an object will undergo when a net force is applied to it

acceleration

If you drop an object, it will accelerate downward at a rate of 9.8 meters per second per second. If you instead throw it downwards, the magnitude of its acceleration (in the absence of air resistance) after leaving your hand will be a) less than 9.8 m/s2 b) 9.8 m/s2 c) greater than 9.8 m/s2

b

The average speed of a horse that gallops a distance of 10 kilometers in a time of 30 minutes is a) 10 km/hr b) 20 km/hr c) 30 km/hr d) more than 30 km/hr

b

When a rock thrown straight upward gets to the exact top of its path, its a) velocity is zero & acceleration is zero b) velocity is zero & its acceleration is about -10 m/s2 c) velocity is 10 m/s and its acceleration is zero d) velocity is 10 m/s & its acceleration is about -10 m/s2

b

As an object freely falls, a) its velocity increases b) its acceleration remains the same c) it does both A & B d) it does neither A nor B

c

Ten seconds after starting from rest, a freely falling object will have a final velocity given by... downward at about a) 10 m/s b) 50 m/s c) 100 m/s d) more than 100 m/s

c

Speed in which equal distances are traveled in equal time intervals is called ______

constant

A car travels around in a circular path at a constant speed. Which of the following statements is true? a) acceleration is zero b) velocity is zero c) A & B are true d) neither A nor B is true

d

An object is in free fall. At one instant, it travels at about 50 meters per second. Exactly one second later, the magnitude of its downward velocity is a) 25 m/s b) 50 m/s c) 55 m/s d) 60 m/s e) 100 m/s

d

Disregarding air resistance, objects fall at a constant a) velocity b) speed c) distance each successive second d) acceleration

d

Suppose you are going on a long bicycle ride. You ride 1 hour at exactly 5 mi/hr. Then you ride 3 hours at exactly 4 mi/hr and then 2 hours at exactly 7 mi/hr. How many miles did you ride? Pretend instantaneous acceleration or de-acceleration between different parts of your ride (that is, no time passes). a) five b) twelve c) fourteen d) thirty one e) thirty six

d

A car accelerates from rest at 3 meters per second per second. What is its speed 5 seconds after it starts moving? a) 2 m/s b) 3 m/s c) 4 m/s d) 6 m/s e) none of these

e

The speed of an object at a particular moment of time, say for a brief moment you look at your car's speedometer, is called ______

instantaneous

If we graph the motion of a tangerine moving at a constant speed on a position-time graph, the magnitude of its speed can be determined by computing the ______ of the line

slope

The amount of distance traveled by an object in a certain amount of time is called the object's ______

speed

Any quantity that requires both magnitude and direction to be fully described is called a(n) ______

vector

The amount of distance traveled by an object in a certain amount of time in a particular direction is called the object's ______

velocity

79.44 m/s is equivalent to ______ mi/hr (round to the 2nd decimal place if necessary)

177.74

The exact (to the 1st decimal place) numerical value and units for acceleration due to gravity on earth is ______

9.8 m/s2

The slope of a line on a velocity-time graph tells us the ______ of an object in motion. (Remember: Slope is rise/run. What would that give you if you applied to a velocity-time graph?)

acceleration

A ball tossed vertically upward rises, reaches its highest point, and then falls back to its starting point. During this time the acceleration of the ball is always a) directed upward b) directed downward c) in the direction of motion d) opposite its velocity

b

Drop a rock from a 5 meter height and it accelerates at 10 m/s/s, striking the ground one second later. Drop the same rock from a height of 2.5 meters and its acceleration of fall compared to the 5 meter height is a) about half b) the same c) about double

b

Galileo's use of inclined planes allowed him to effectively a) eliminate the acceleration due to gravity b) decrease the acceleration due to gravity c) increase the acceleration due to gravity d) deal with none of these

b

A paintball if shot straight up at a velocity of 60 m/s. Assuming that air resistance can be ignored, the time it takes to reach the top of its path is about a) 0.5 second b) 1 second c) 2 seconds d) 10 seconds e) none of these

e

If a car increases its velocity from zero to 60 km/hr in 10 seconds, its acceleration is a) 2 km/s b) 3 km/s c) 4 km/s d) 6 km/s e) none of these

e