Deck 3: Acceleration and Newtons Second Law of Motion

Question 1

A car travels for 140 km at 70.0 km/hr.It then travels an additional distance of 60.0 km 40.0 km/hr.The average speed is

A) 61.0 km/hr.
B) 57.1 km/hr.
C) 53.3 km/hr.
D) 46.7 km/hr.
E) 45.0 km/hr.

Answer 1

57.1 km/hr.

Question 2

The graph shows v_x versus t for an object moving along straight line.What is the average velocity from t = 0 to t = 11 s?

A) 25 m/s²
B) 36 m/s²
C) 30 m/s²
D) 21 m/s²

Answer 2

25 m/s²

Question 3

An ant travels 30 cm east,25 cm north,and finally 15 cm west.What is the direction with respect to its starting point?

A) 59 $^{\circ}$ N of E
B) 77 $^{\circ}$ N of E
C) 29 $^{\circ}$ N of E
D) 59 $^{\circ}$ N of W

Answer 3

59 $^{\circ}$ N of E

Question 4

If an object is located 20 m to the left of the origin at 1:00 PM,and later the object is located 30 m to the right of the origin at 2:00 PM,then the displacement from 1:00 PM to 2:00 PM is

A) 50 m to the right.
B) 30 m to the right.
C) 25 m to the right.
D) 20 m to the left.
E) 10 m to the left.

Question 5

A car travels at 50.0 km/hr for 2.00 hours.It then travels an additional distance of 40.0 km in 1.00 hour.The average speed of the car for the entire trip is

A) 61.0 km/hr.
B) 57.1 km/hr.
C) 53.3 km/hr.
D) 46.7 km/hr.
E) 30.0 km/hr.

Question 6

The graph shows v_x versus t for an object moving in a straight line.What is the average velocity from t = 0 s to t = 9 s?

A) 44 m/s²
B) 32 m/s²
C) 22 m/s²
D) 24 m/s²

Question 7

A displacement vector D is given as 40.0 m long at an angle of 60.0 degrees NORTH of EAST.The D_x component and the D_y component of the vector are

A) D_x = +34.6 m,D_y = +20.0 m.
B) D_x = +20.0 m,D_y = -34.6 m.
C) D_x = +20.0 m,D_y = +34.6 m.
D) D_x = -34.6 m,D_y = +20.0 m.
E) D_x = +34.6 m,D_y = -20.0 m.

Question 8

A displacement vector D is given as 40.0 m long at an angle of 60.0 degrees EAST of NORTH.The D_x component and the D_y component of the vector are

A) D_x = +34.6 m,D_y = +20.0 m.
B) D_x = +20.0 m,D_y = -34.6 m.
C) D_x = +20.0 m,D_y = +34.6 m.
D) D_x = -34.6 m,D_y = +20.0 m.
E) D_x = +34.6 m,D_y = -20.0 m.

Question 9

If an object is located 20 m to the right of the origin at 1:00 PM,and later the object is located 30 m to the left of the origin at 2:00 PM,then the displacement from 1:00 PM to 2:00 PM is

A) 50 m to the right.
B) 50 m to the left.
C) 30 m to the right.
D) 30 m to the left.
E) 10 m to the left.

Question 10

If an object is located 20 m to the right of the origin at 1:00 PM,and later the object is located 30 m to the right of the origin at 2:00 PM,then the displacement from 1:00 PM to 2:00 PM is

A) 50 m to the right.
B) 30 m to the right.
C) 25 m to the right.
D) 20 m to the right.
E) 10 m to the right.

Question 11

The figure shows the graph of v_x versus time for an object moving along the x-axis.Solve graphically for the distance traveled from t = 9.0 s to t = 13.0 s.

A) 60 m
B) 84 m
C) 76 m
D) 80 m

Question 12

You drive five blocks due north,five blocks due east,and another two blocks due north.What is the magnitude of your displacement?

A) 7 blocks
B) 12 blocks
C) 9 blocks
D) 10 blocks
E) 8.6 blocks

Question 13

The figure is a graph of an object moving in a straight line.Solve graphically to determine which section of the path has the highest speed.

A) DE
B) EF
C) CD
D) AB

Question 14

The figure is a graph of v_x(t)for a car.Solve graphically for the distance traveled from t = 10 s to t = 15 s.

A) 75 m
B) 70 m
C) 67 m
D) 69 m

Question 15

The figure is a graph of the vertical velocity versus time for an elevator.Solve graphically for the height of the elevator above the starting point at t = 20 s.

A) 4.0 m
B) 16.0 m
C) 0.0 m
D) 8.0 m

Question 16

Which of the following specifications would allow you to precisely meet someone for an appointment?

A) meet me at my car
B) meet me at my office,room 203 in Williams Hall on campus
C) meet me at my office,room 203 in Williams Hall on campus at 2:30 PM
D) meet me at my office
E) meet me at 2:30 PM

Question 17

The graph shows the speedometer reading of a car as it comes to a stop along a straight-line path.How far does the car move between t = 0 s and t = 16 s?

A) 130 m
B) 140 m
C) 150 m
D) 160 m

Question 18

A car travels a distance of 100 km in 2.00 hours.It then travels an additional distance of 60.0 km in 1.00 hour.The average speed of the car for the entire trip is

A) 80.0 km/hr.
B) 60.0 km/hr.
C) 53.3 km/hr.
D) 50.0 km/hr.
E) 46.7 km/hr.

Question 19

The graph shows v_x versus t for an object moving along straight line.What is the acceleration at t = 11 s?

A) -10 m/s²
B) 10 m/s²
C) 22 m/s²
D) -22 m/s²

Question 20

Displacement is

A) the distance traveled from the first position to the final position.
B) the distance from the origin to the final position.
C) the change of the position vector from the first position the final position.
D) the vector from the origin to the final position.

Question 21

A tractor T is pulling a trailer M with a constant acceleration.If the forward acceleration is 0.50 m/s² and M = 400 kg and T = 500 kg,then the horizontal force on the tractor due to the ground is

A) 450 N forward.
B) 450 N backward.
C) 250 N forward.
D) 250 N backward.
E) 200 N forward.

Question 22

A tractor of mass M₁ = 2,000 kg is pulling a trailer of mass M₂ = 5,000 kg.If the tractor-trailer is accelerated at 2.0 m/s²,then the tension in the trailer hitch that connects the trailer to the tractor is

A) 6,000 N.
B) 8,000 N.
C) 9,000 N.
D) 10,000 N.
E) 11,000 N.

Question 23

Two masses are suspended by cord that passes over a pulley with negligible mass.The cord also has negligible mass.One of the masses,m₁,has a mass of 6.0 kg and the other mass,m₂,has a mass of 4.0 kg.The force of the cord attached to m₁ is

A) 47 N upward.
B) 47 N downward.
C) 33 N upward.
D) 33 N downward.
E) 15 N upward.

Question 24

A tractor T is pulling two trailers,M₁ and M₂,with a constant acceleration.T has a mass of 200 kg,M₁ has a mass of 100 kg,and M₂ has a mass of 150 kg.If the forward acceleration is 0.60 m/s²,then the horizontal force on the tractor due to the ground is

A) 270 N backward.
B) 270 N forward.
C) 150 N backward.
D) 150 N forward.
E) 90 N forward.

Question 25

A tractor T is pulling a trailer M with a constant acceleration.If the forward acceleration is 1.5 m/s² and M = 400 kg and T = 500 kg,then the force on the tractor due to the trailer is

A) 600 N backward.
B) 450 N backward.
C) 200 N forward.
D) 35 N forward.
E) 0.

Question 26

In the figure,an airport luggage-carrying train with a tractor T is pulling three luggage carts,M₁,M₂,and M₃ with an acceleration of 1.2 m/s².If T = 300 kg,M₁ = 200 kg,M₂ = 100 kg,and M₃ = 100 kg,then the force in the connection between cart M₂ and cart M₁ is

A) 840 N.
B) 480 N.
C) 240 N.
D) 120 N.
E) 0 N.

Question 27

The figure shows the graph of v_x versus time for an object moving along the x-axis.What is the acceleration at t = 7.0 s?

A) 4.0 m/s²
B) 5.0 m/s²
C) 0.5 m/s²
D) 0.4 m/s²

Question 28

A tractor T is pulling two trailers,M₁ and M₂,with a constant acceleration.T has a mass of 200 kg,M₁ has a mass of 100 kg,and M₂ has a mass of 150 kg.If the forward acceleration is 0.60 m/s²,then the horizontal force on M₂ due to the attachment to M₁ is

A) 270 N backward.
B) 270 N forward.
C) 150 N backward.
D) 150 N forward.
E) 90 N forward.

Question 29

In the figure,an airport luggage-carrying train with a tractor T is pulling three luggage carts,M₁,M₂,and M₃ with an acceleration of 1.0 m/s².If T = 300 kg,M₁ = 200 kg,M₂ = 100 kg,and M₃ = 100 kg,then the force in the connection between cart M₂,and cart M₃ is

A) 700 N.
B) 400 N.
C) 200 N.
D) 100 N.
E) 0 N.

Question 30

Two masses are connected by a cord that passes over a pulley as shown in the figure.The pulley and the cord have negligible mass and m₂ (6.0 kg)moves on a horizontal surface with a coefficient of friction of 0.5,m₁ (2.0 kg)is suspended vertically.What is the acceleration of m₂?

A) 0.0 m/s²
B) 3.0 m/s²
C) 1.0 m/s²
D) 2.9 m/s²

Question 31

The figure shows the speedometer readings as a car comes to a stop.Solve graphically for the acceleration at t = 7.0 s.

A) 2.5 m/s²
B) - 2.5 m/s²
C) - 2.0 m/s²
D) 2.0 m/s²

Question 32

A tractor T is pulling a trailer M with a constant velocity.If the velocity is 20 m/s and M = 200 kg and T = 500 kg,then the force on the trailer due to the tractor is

A) 600 N forward.
B) 450 N backward.
C) 200 N backward.
D) 35 N forward.
E) 0.

Question 33

A tractor of mass M₁ = 2,000 kg is pulling a trailer of mass M₂ = 5,000 kg.If the tractor-trailer is accelerated at 2.0 m/s²,then the force the tractor applies to the road is

A) 14,000 N.
B) 12,000 N.
C) 10,000 N.
D) 8,000 N.
E) 6,000 N.

Question 34

A 4.0 kg mass has a velocity of 12 m/s to the WEST.The 4.0 kg mass undergoes an acceleration of 2.0 m/s² to the WEST for 3.0 sec.What is the velocity of the 4.0 kg mass at the end of the 3.0 sec interval?

A) 18 m/s to the WEST
B) 6.0 m/s to the WEST
C) 0.0 m/s
D) 6.0 m/s to the EAST
E) 18 m/s to the EAST

Question 35

An object starts from rest with an acceleration of 2.0 m/s² for 3.0 seconds.It then reduces its acceleration to 1.0 m/s² for 5.0 additional seconds.The velocity at the end of the 5.0 seconds interval is

A) 6.0 m/s.
B) 18. m/s.
C) 8.0 m/s.
D) 18 m/s.
E) 11 m/s.

Question 36

Two masses are connected by a cord that passes over a pulley as shown in the figure.The pulley and cord have negligible mass and m₁ (2.0 kg)moves on a horizontal surface without friction,m₂ (2.0 kg)is suspended vertically.What is the acceleration of m₁?

A) 3.9 m/s²
B) 12 m/s²
C) 6.0 m/s²
D) 4.9 m/s²

Question 37

A tractor T is pulling two trailers,M₁ and M₂,with a constant acceleration.T has a mass of 200 kg,M₁ has a mass of 100 kg,and M₂ has a mass of 150 kg.If the forward acceleration is 0.60 m/s²,then the horizontal force on the tractor due to the attachment to M₁ is

A) 270 N backward.
B) 270 N forward.
C) 150 N backward.
D) 150 N forward.
E) 90 N forward.

Question 38

Two masses are suspended by a cord that passes over a pulley with negligible mass.The cord also has negligible mass.One of the masses,m₁,has a mass of 7.0 kg and the other mass,m₂,has a mass of 3.0 kg.The pulley turns on a shaft through the center of the pulley and supports the pulley and all the masses.The vertical force of the shaft on the pulley that supports the whole system is

A) 49 N upward.
B) 49 N downward.
C) 82 N upward.
D) 82 N downward.
E) 98 N upward.

Question 39

Two masses are suspended by cord that passes over a pulley with negligible mass.The cord also has negligible mass.One of the masses,m₁,has a mass of 5.0 kg and the other mass,m₂,has a mass of 3.0 kg.The acceleration of m₁ is

A) 3.3 m/s² upward.
B) 3.3 m/s² downward.
C) 2.5 m/s² upward.
D) 2.5 m/s² downward.
E) 1.1 m/s² upward.

Question 40

An object starts from rest with an acceleration of 2.0 m/s² for 3.0 seconds.It then reduces its acceleration to 1.0 m/s² for 5.0 additional seconds.The total distance covered is

A) 52 m.
B) 38 m.
C) 11 m.
D) 9.0 m.
E) 7.6 m.

Question 41

The velocity of a boat with respect to the water is 4.0 m/s at an angle of 30.0 degrees NORTH of WEST.The velocity of the water with respect to the ground is 8.0 m/s at an angle of 45 degrees SOUTH of EAST.What is the velocity of the boat with respect to the ground?

A) 4.7 m/s at 32 degrees SOUTH of WEST
B) 4.3 m/s at 59 degrees SOUTH of EAST
C) 8.3 m/s at 22 degrees SOUTH of WEST
D) 9.8 m/s at 330 degrees SOUTH of EAST
E) 8.3 m/s at 25 degrees SOUTH of WEST

Question 42

An airplane is flying in horizontal flight at a constant acceleration of 2.00 m/s².The weight of the airplane is 40,000 N.The wings produce a lift force that is perpendicular to the wings and a drag force which is parallel to the wing is 2,000 N.The forward thrust force the engine produces is

A) 2,800 N.
B) 4,000 N.
C) 7,500 N.
D) 8,000 N.
E) 10,200 N.

Question 43

An object starts with an initial velocity of 4.0 m/s and accelerates with an acceleration of +4.0 m/s² for 6.0 seconds.It then decelerates at -2.0 m/s² until its velocity is 4.0 m/s.The total distance covered is

A) 67 m.
B) 94 m.
C) 105 m.
D) 192 m.
E) 215 m.

Question 44

A runner starts from rest and with an acceleration of 2.0 m/s² travels a distance of 12 meters.The velocity of the runner at the end of the distance is

A) 3.4 m/s.
B) 5.7 m/s.
C) 6.9 m/s.
D) 7.5 m/s.
E) 8.1 m/s.

Question 45

A boat is traveling at 4.0 m/s as it passes the starting line of a race.If the boat accelerates at 1.0 m/s² for 6.0 seconds,then the average velocity of the boat for the 6.0 seconds is

A) 21 m/s.
B) 9.0 m/s.
C) 13 m/s.
D) 10 m/s.
E) 7.0 m/s.

Question 46

A car starts from rest and travels a distance of 100 m in 10 seconds.The acceleration of the car is

A) 1.0 m/s².
B) 2.0 m/s².
C) 2.5 m/s².
D) 3.0 m/s².
E) 3.5 m/s².

Question 47

A 2.0 kg object is moving at a velocity of 12.0 m/s.The drag force 6.0 N.If the drag force is given by the equation F = bv²,then the value of b is

A) 1.5 $\times$ 10^-2 Ns²/m².
B) 4.2 $\times$ 10^-2 kg/m.
C) 3.9 $\times$ 10^-1 kg/m².
D) 4.2 $\times$ 10^-1 N/m².
E) 7.5 $\times$ 10^-3 Ns²/m².

Question 48

A car traveling at 4.0 m/s has a constant acceleration of 2.0 m/s².After 3.0 seconds,the distance traveled during the acceleration is

A) 21 m.
B) 17 m.
C) 10 m.
D) 13 m.
E) 9 m.

Question 49

A boat is traveling at 4.0 m/s as it passes the starting line of a race.If the boat accelerates at 2.0 m/s² for 3.0 seconds,then the velocity the boat has after the 3.0 seconds is

A) 21 m/s.
B) 9.0 m/s.
C) 13 m/s.
D) 10 m/s.
E) 4.0 m/s.

Question 50

A car starting from rest travels a distance of 20.0 m with a constant acceleration of 2.0 m/s².The car then slows to a stop in 10.0 seconds with a constant negative acceleration.The distance traveled by the car is

A) 36 m.
B) 46 m.
C) 50 m.
D) 58 m.
E) 65 m.

Question 51

A 4.0 kg mass has a velocity of 10 m/s to the EAST.The 4.0 kg mass undergoes an acceleration of 4.0 m/s² to the WEST for 3.0 sec.What is the velocity of the 4.0 kg mass at the end of the 3.0 sec interval?

A) 22 m/s to the WEST
B) 2.0 m/s to the WEST
C) 0.0 m/s
D) 2.0 m/s to the EAST
E) 22 m/s to the EAST

Question 52

A car starts from rest and travels a distance of 100 m in 20 seconds with a constant acceleration.The velocity of the car is at the end of the 20 second interval is

A) 25 m/s.
B) 20 m/s.
C) 15 m/s.
D) 10 m/s.
E) 5.0 m/s.

Question 53

A car traveling at 4.0 m/s has a constant acceleration of 2.0 m/s².After 3.0 seconds,the average velocity during the acceleration is

A) 5.0 m/s.
B) 7.0 m/s.
C) 9.0 m/s.
D) 11 m/s.
E) 13.

Question 54

A car traveling at 3.0 m/s has a constant acceleration of 4.0 m/s².After 2.0 seconds,the velocity is

A) 5.0 m/s.
B) 7.0 m/s.
C) 9.0 m/s.
D) 11 m/s.
E) 13 m/s.

Question 55

A runner starts from rest and with an acceleration of 1.0 m/s² travels a distance of 10 meters.The time it takes the runner to cover the distance is

A) 6.3 s.
B) 5.7 s.
C) 5.0 s.
D) 4.5 s.
E) 3.8 s.

Question 56

An 80.0 kg person is riding in an elevator that is accelerating at 2.40 m/s² downward.The apparent weight of the 80.0 kg person measured on a scale in the elevator is

A) 592 N.
B) 639 N.
C) 784 N.
D) 855 N.
E) 976 N.

Question 57

A car starts from rest and travels a distance of 100 m in 15 seconds with a constant acceleration.The average velocity of the car for the 15 seconds interval is

A) 24.0 m/s.
B) 21.0 m/s.
C) 16.7 m/s.
D) 13.3 m/s.
E) 6.67 m/s.

Question 58

An object starts from rest and moves with an acceleration of 2.0 m/s² for 3.0 seconds.It then reduces its acceleration to 1.0 m/s² for 5.0 additional seconds.The velocity 8 seconds from the start of the motion is

A) 51 m/s.
B) 38 m/s.
C) 11 m/s.
D) 9.0 m/s.
E) 7.6 m/s.

Question 59

A boat is traveling at 4.0 m/s as it passes the starting line of a race.If the boat accelerates at 1.0 m/s² for 6.0 seconds,then the distance the boat has traveled after 6.0 seconds is

A) 42 m.
B) 18 m.
C) 26 m.
D) 20 m.
E) 14 m.

Question 60

The velocity of a boat with respect to the water is 4.0 m/s at an angle of 30.0 degrees NORTH of EAST.The velocity of the water with respect to the ground is 3.0 m/s at an angle of 90.0 degrees NORTH of EAST.What is the velocity of the boat with respect to the ground?

A) 6.1 m/s at 36 degrees NORTH of EAST
B) 5.8 m/s at 55 degrees NORTH of EAST
C) 6.1 m/s at 61 degrees NORTH of EAST
D) 5.8 m/s at 36 degrees NORTH of EAST
E) 6.1 m/s at 55 degrees NORTH of EAST

Question 61

A river flows toward the East at 1.7 m/s.Steve can swim 2.0 m/s in still water.If he swims,relative to the water at a direction of 33 degrees west of north,how long will it take him to cross the 75 m wide river?

A) 45 s
B) 39 s
C) 123 s
D) 27 s

Question 62

A model airplane is flying north at 12.5 m/s initially - and 25 seconds later is observed heading 30 degrees west of north at 25 m/s.What is the magnitude of the average acceleration during this time interval?

A) 0.37 m/s²
B) 0.50 m/s²
C) 0.62 m/s²
D) 0.87 m/s²

Question 63

A river flows toward the East at 2.2 m/s.Steve can swim 2.5 m/s in still water.If he wishes to cross the river so that his direction is northward,how long will it take him to cross the 75 m wide river?

A) 34 s
B) 39 s
C) 30 s
D) 63 s

Question 64

A beetle runs an erratic pattern on a square kitchen table that is 1.5 m on a side.The sides are arranged along the directions North/South and East/West.If he begins at the Southwest corner,and travels along one side to the adjacent corner in 20.0 s.He then turns north,and reaches the Northeast corner 12.5 s later.What is the magnitude of his average velocity for the whole trip?

A) 0.092 m/s
B) 0.098 m/s
C) 0.065 m/s
D) 0.033 m/s

Question 65

A 450 g baseball is pitched,reaching the batter with a speed of 37 m/s and is hit such that it returns on the same line at 48 m/s.If the ball was in contact with the bat for 0.22 seconds,what was the average net force experienced by the ball during the time of contact?

A) 170 N
B) 98 N
C) 77 N
D) 18 N

Question 66

A river flows toward the East at 1.5 m/s.Steve can swim 2.2 m/s in still water.If he wishes to cross the river so that his direction is northward,what direction relative to the water must he swim?

A) 55 $^{\circ}$ north of west
B) 43 $^{\circ}$ west of north
C) 34 $^{\circ}$ north of west
D) 47 $^{\circ}$ west of north

Question 67

An object travels 7.5 m/s toward the West and under the influence of a constant net force of 5.2 kN,4.3 s later,it is travelling 2.5 m/s toward the East.What is its mass?

A) 2200 kg
B) 4500 kg
C) 6000 kg
D) 12000 kg

Question 68

An ant crawls in a straight line at a constant speed of 0.24 m/s for a distance of 3.0 m,beginning in the corner of a square classroom.It then turns exactly 90 degrees to the right,and proceeds an additional 4.0 m with a constant speed of 0.44 m/s,reaching the other corner of the same wall from which it began.What was the average speed for the full trip from corner to corner?

A) 0.34 m/s
B) 0.30 m/s
C) 0.21 m/s
D) 0.23 m/s
E) 0.32 m/s

Question 69

An ant crawls in a straight line at a constant speed of 0.24 m/s for a distance of 3.0 m,beginning in the corner of a square classroom.It then turns exactly 90 degrees to the right,and proceeds an additional 4.00 m,reaching the far corner of the same wall from which it began.If the second leg was also crawled in half the amount of time as required for the first leg,what was the ant's average speed for the whole trip?

A) 0.80 m/s
B) 0.27 m/s
C) 0.37 m/s
D) 0.44 m/s

Question 70

You drive your car 5.0 km due East at 35 km/hr,and suddenly realize that you forgot your wallet.So,you return home,driving West at 40 km/hr,and upon arrival spend 10 minutes looking for it,and finally go back on the road for a total of 57.0 km due East.If your average velocity was 40 km/hr for the whole journey,what was your average speed on your last leg.

A) 49 km/hr
B) 40 km/hr
C) 45 km/hr
D) 56 km/hr

Question 71

An object travels 7.5 m/s toward the West and under the influence of a constant net force of 5.2 kN,it comes to rest in 3.2 s.What is its mass?

A) 1600 kg
B) 12000 kg
C) 1100 kg
D) 690 kg

Question 72

The velocity of an airplane with respect to the ground is 2.00 $\times$ 10² m/s at an angle of 30.0 degrees NORTH of EAST.The velocity of the airplane with respect to the air is 1.50 $\times$ 10² m/s at an angle of 60.0 degrees NORTH of EAST.What is the velocity of the air with respect to the ground?

A) 112 m/s at 50.0 degrees NORTH of EAST
B) 102 m/s at 17 degrees SOUTH of EAST
C) 134 m/s at 49 degrees SOUTH of EAST
D) 134 m/s at 17 degrees NORTH of EAST
E) 102 m/s at 65 degrees NORTH of EAST

Question 73

A baseball is pitched,reaching the batter with a speed of 37 m/s and is hit such that it returns on the same line at 48 m/s.If the ball was in contact with the bat for 0.22 seconds,what was the average acceleration experienced by the ball during the time of contact?

A) 220 m/s²
B) 41 m/s²
C) 390 m/s²
D) 170 m/s²

Question 74

A 78.0 kg object is travelling due North at 15.2 m/s,and experiences a constant net force of 1.72 kN toward the South.How long will it take to stop under the influence of this force?

A) 1.45 s
B) 2.98 s
C) 0.335 s
D) 0.689 s

Question 75

An ant crawls in a straight line at a constant speed of 0.35 m/s,beginning in the corner of a square classroom that is 5.00 m on a side.It first crosses the diagonal of the room,and then turns to the right,continuing at 0.45 m/s to the far corner of the same wall from which it began.What was the ant's average speed for the whole trip?

A) 0.40 m/s
B) 0.16 m/s
C) 0.24 m/s
D) 0.39 m/s

Question 76

A 1.7 kg model airplane is flying north at 12.5 m/s initially - and 25 seconds later is observed heading 30 degrees west of north at 25 m/s.What is the magnitude of the average net force on the airplane during this time interval?

A) 0.85 N
B) 0.63 N
C) 1.1 N
D) 1.5 N

Question 77

The interstate on-ramp is 5.5 km West of your home,and on leaving for grandmother's house you are only able to accomplish an average velocity of 38 km/hr between your home and the on-ramp.At the on-ramp,you wait for traffic,for 2.0 min - and then are able to proceed toward grandmother's house.If you wish to arrive there,which is 15 km South of the on-ramp,over a river and through some woods,having achieved an average velocity of 42 km/hr,how fast do you need to drive south on the interstate highway?

A) 58 km/hr
B) 48 km/hr
C) 78 km/hr
D) 39 km/hr

Question 78

The velocity of the air with respect to the ground is 50.0 m/s at an angle of 30.0 degrees NORTH of EAST.The velocity of the airplane with respect to the air is 150 m/s at an angle of 60.0 degrees NORTH of EAST.What is the velocity of the airplane with respect to the ground?

A) 158 m/s at 16 degrees NORTH of EAST
B) 103 m/s at 29 degrees SOUTH of EAST
C) 200 m/s at 30 degrees NORTH of EAST
D) 135 m/s at 29 degrees SOUTH of EAST
E) 200 m/s at 30 degrees SOUTH of EAST

Question 79

The interstate on-ramp is 1.5 km West of your home,and on leaving for grandmother's house you are only able to accomplish an average velocity of 12 km/hr between your home and the on-ramp.At the onramp,you wait for traffic,for 2.0 min - and then are able to proceed toward grandmother's house.If you wish to arrive there,which is 15 km South of the onramp,over a river and through some woods,in a total elapsed time of 25.0 minutes,what average speed must you maintain on the interstate highway?

A) 51 km/hr
B) 67 km/hr
C) 36 km/hr
D) none of these.