11 Test
A truck traveled 400 meters north in 80 seconds , and then it traveled 300 meters east in 70 seconds . What is the average speed of the truck ?
4.7 m / s
41. A person traveled by train for 1.0 hr at a speed of 50.0 km / h . He then traveled by a taxi for 30 minutes at a speed of 32.0 km / h to complete his journey . What is the average speed at which he traveled during the journey ?
44 km / h
29. A cyclist rides a bicycle 4.0 km West , then 3.0 km North . What was the total displacement traveled ?
5.0 Km [NW]
A student walks 30m [ E ] , 15m [ W ] , and then 40m [ E ] . What is the student's total displacement
55 m [ E ]
20. John walks 4.0 km [ East ] and then turns and runs 3.0 km [ South ] . What is John's total distance ?
7.0 km
Dexter is travelling on his bike 4 m / s [ S ] . If he accelerates at a rate of 1.5 m / s² [ S ] for 25 . what is his final velocity ( A
7.0 m / s [ S]
A running football player has a change in velocity of 9.80 m / s [ N ] in 1.4 s . What is his average acceleration
7.0 m / s² [ N ]
An object accelerates at 2.2 m / s² for 3.0 s . If the final velocity of the object is 15 m / s , what was the initial velocity ?
8.4 m / s
A car travels [ North ] at 100 km / h for 1.0 hour then turns and travels [ South ] at 70 km / h for 2.0 h . What is the average speed for the trip ?
80.0 km / h
24. A ball is thrown vertically up and is caught at the starting point ; what is the displacement of the ball ?
A ) 0
refers to the rate at which velocity changes ?
Acceleration
What does the term " acceleration of 5 m / s² " mean ?
An object travels 5m / s faster each second
What is the average velocity of a car that moved 40 km East and 80 km West in 2 hours ?
B ) 20 km / h [ West ]
A car travels 30 km at an average speed of 60 km / hr and then 30 km at an average speed of 30 km / hr . What is the average speed of the car over 60 km ?
B ) 40 km / hr
What is the SI unit for speed ?
B ) m/s
Which terms describes speed at a particular moment in time ?
Instantaneous Speed
If the velocity vector is directed to the right and the acceleration vector is dire left , then the object is :
Moving to the right and slowing down
Which of the following pairs are both scalar quantities ?
Speed and mass
Which statement is true ?
displacement can never be greater than distance
Which of the following best describes the speed of an object ?
distance it travels divided by the time it takes
What is the distance for the same ball in question # 24 ?
double the height
Which of the following is a physical quantity that has a magnitude but no direction ?
scalar
What quantity do you get from the slope of a d - t graph ?
speed
What is the name of the instrument used to measure instantaneous speed of a vehicle .
speedometer
Which of the following would represent uniform motion on a distance - time graph ?
straight line
A car travels 10 km [ North ] then turns and goes 8 km [ South ] . Which statement is correct ?
the distance is 18 km and the displacement is 2 km .
When is an object accelerating ?
when its speed or direction changes .
A car travels 90 km / h . How long does it take for it to travel 400 km ?
4.4 h
30. Tom throws a baseball with an average speed of 150km / h . Calculate the time in hours for the ball to travel over a distance of 20m .
( D ) 0.00013h
What is the speed of a bird that flies 6.0 m in 2.0 s ?
) 3.0 m / s
A girl runs once around a circular track with a radius of 65m at a speed of 2.0 m / s . What distance did she cover ?
) 410m
Which of the following is a vector quantity ?
) 65 m / s [ E ]
The speedometer in a car indicates
) a scalar quantity .
A baseball is traveling at +65 km / h and is caught by a player . The ball is brought to rest in 0.5 s . What is the acceleration of the ball ?
-36 m / s²
22 A car moves to the right 100 m then goes to the left for 150 m . What is the displacement ( assuming motion to the right is positive ) ?
-50 m .
Scalar and vector
-Scalar: magnitude -Vector: magnitude and direction
boy runs once around a circular track with a radius of 45m at a speed of 2.5 m / s . What is the boys displacement ?
0
An object travels with uniform motion at 20 m / s for 10 s . What is the acceleration ?
0 m / s^2
what is 1.0km/hr equal to
0.28 m/s
A car increases its speed from 9.6 m / s to 11.2 m / s in 4.0 s . What is the average acceleration of the car during this 4.0 s interval ?
0.40 m / s²
A soccer ball takes 20 s to roll 10 m . What is the average speed of the soccer ball ?
0.5 m/s
A boat goes 15 km [ North ] then turns and goes 10 km [ South ] . The trip takes 5 hours . What is the average velocity ?
1.0 km / h
What is the distance covered by a car in 5 h if it is moving with a speed of 35 km / h ?
175 km )
49. A runner takes 2.5 min to complete one lap around a circular track with a diameter of 100.0 m What was the average speed of the runner ? m / s
2.1 m / s
Which of the following quantities could specify an acceleration vector ?
2.5 m / s² [ E ]
What is the average speed of a car that travels a distance of 10 km in 30 min ?
20 km / h
If a car has a constant acceleration of 4 m s² , starting from rest , how fast is it traveling after 5 seconds ?
20 m / s
If a car accelerates from 3.0 m / s to 12 m / s in 3.0 seconds , what is the car's average acceleration
3.0 m / s²
Molly runs two laps of a 400 m running track The first lap takes 150 seconds and the second lap takes 80 seconds . What is her average speed over the two laps ?
3.5 m / s
If an object accelerates at 1.2 m / s2 [ N ] , how long will it take to reach a velocity of 5.0 m / s [ N ] if starting from rest
4.2 s