science speed and acceleration study guide
what is the most appropriate SI unit to express the speed of a cyclist in the last leg of a 10 km race
km/hr
the relationship among speed,distance, and time is
v=d/t
3 m/s north is an example of a
velocity
acceleration is rate of change of
velocity
give an example describes constant acceleration due ONLY to a change in direction
windmill
the equation used to find acceleration is a=
(vf-vi)/t
a cross country runner runs 10km in 40 min. what is his average speed
.25 km/min
a person walks 1 mile everyday for exercise leaving her front porch at 9 am and returning to her front porch at 9:25. what is the total displacement of her daily walk
0
a distance time graph indicates that an object moves 100 m in 4 s and then remains at rest for 6s. what is the average speed of the object
10 m/s
during a race, a runner runs at a speed of 6 m/s. 2s later she is running at a speed of 10m/s. what is the runners acceleration?
2 m/s2
what is the speed of a bobsled whose distance time graph indicates that it travels 100 m in 25s
4 m/s
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 a rest against a tree. what is the magnitude of the balls displacement
4 meters
a car traveled 60 km in 2 hrs 84 km in the next hr and then 68km in 2hrs before reaching its destination. what is the cars average speed
42.4 km/hr
a high speed train travels with an average speed of 227km/hr. the train travels for 2 hrs. how far does the train travel
454 km/hr
a truck travels to and from a stone quarry that is located 2.5 km to the east. what is its distance, displacement?
5 km, 0
if you ride your bike at an average speed of 4 km/hr and need to travel a total distance of 28 km, how long will it take you to reach your destination
7hrs
find the acceleration of a car that goes from 32 m/s to 96 m/s in 8s
8 m/s2
suppose you increase your walking speed from 1 m/s to 3 m/s in a period of 1s. What is your acceleration
a=2m/s2
An object moving at 30 m/s takes 5s to come to a stop. What is the objects acceleration
a=6m/s2
the rate at which velocity is called
acceleration
instantaneous speed is measured
at an instant
motion is a change in
change in position
a train approaching a crossing changes speed from 25 m/s to 10 m/s in 240s. How can the trains acceleration be described
deceleration
a merry-go-round horse moves at a constant speed but at a changing
direction
two cars start at the same point and drive in a straight line for 5 km. at the end of the drive their distance are the same but their displacement are different. how?
going in a different direction
if your ride your bicycle down a straight road for 500 m then turn around and ride back, your distance is ___ your displacement
greater than
the speed you read on a speedometer is
instantaneous speed
if you ride your bike uphill then ride it down the other side, your acceleration is
negative, positive
give an example that identifies a change in motion that produces acceleration
plane taking off
what is something you could most accurately measured with a ruler
shoe
a car has an acceleration of -5 m/s2. the cars motion is best described as ____
slowing down
an object that is accelerating may be ______, _______, or ______
speed up, slow down, and changing direction
an inline skater is skating around a parking lot can have constant ___ but changing ____
speed, direction
a horizontal line on a distance time graph means the object is
stopped
a person drives north 6 blocks then turns west and drives 6 blocks. the driver then turns south and drives 6 blocks. how could the driver have made the distance shorter while maintaining the same displacement
west 6 blocks