1. A highway curve has a radius of 0. 59 km and is unbanked
A highway curve has a radius of 0.59 km and is unbanked. A car weighing 26 kN goes around the curve at a speed of 39 m/s without slipping. What is the magnitude of the horizontal force of the road on the car? Select the correct answer.
6.8 kN
33 kN
19 kN
29 kN
26 kN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

2. A 6.5-kg mass on the end of a string rotates in a circular motion on a horizontal frictionless table. The mass has a constant speed of 2.1 m/s and the radius of the circle is 0.76 m. What is the magnitude of the resultant force acting on the mass? Select the correct answer.
38 N
60 N
64 N
74 N
0 N 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

3. both containers slide off the turntable at the same turntable speed
Two small cylindrical plastic containers with flat bottoms are placed on a turntable that has a smooth flat surface. Canister B is empty, canister A contains lead shot. Each canister is the same distance r from the center. The coefficient of static friction between the canisters and the turntable is μs. When the speed of the turntable is gradually increased, _____ . Select the correct answer.
both containers slide off the turntable at the same turntable speed
only the lighter container slides outward off the turntable; the heavier one stays on
only the heavier container slides outward off the turntable; the lighter one stays on
the lighter container slides inward
the heavier container slides inward 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

4. 4.7 kN up 3.7 kN down 3.7 kN up 7.3 kN down 4.2 kN up
A stunt pilot weighing kN performs a vertical circular dive of radius 0.36 km. At the bottom of the dive, the pilot has a speed of km/s which at that instant is not changing. What force does the plane exert on the pilot? Select the correct answer.
4.7 kN up
3.7 kN down
3.7 kN up
7.3 kN down
4.2 kN up 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

5. A kg mass attached to the end of a string swings in a vertical circle ( R = 7.8 m), as shown. At an instant when Θ = 59° the tension in the string is 7.0 N. What is the magnitude of the resultant force on the mass at this instant? Select the correct answer.
6.4 N
4.1 N
4.9 N
5.7 N
9.0 N 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

6. down, inwards and backwards
A hornet circles around a pop can at increasing speed while flying in a path with a 12-cm diameter. We can conclude that the hornet's wings must push on the air with force components that are _____ . Select the correct answer.
down and outwards
straight down
down and inwards
down and backwards
down, inwards and backwards 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

7. When a bus goes around a circular curve on a level road, _____
When a bus goes around a circular curve on a level road, _____ . Select the correct answer.
no frictional force is needed because the bus simply follows the road
the frictional force of the road on the bus increases when the bus's speed decreases
the frictional force of the road on the bus increases when the bus's speed increases
the frictional force of the road on the bus increases when the bus moves to the outside of the curve
there is no net frictional force because the road and the bus exert equal and opposite forces on each other 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

8. A 0.86 kg mass attached to the end of a string swings in a vertical circle (radius = 2.6 m). When the mass is at the highest point of the circle the speed of the mass is 8.8 m/s. What is the magnitude of the force of the string on the mass at this position? Select the correct answer.
17 N
34 N
54 N
69 N
26 N 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

9. An airplane moves 140 m/s as it travels around a vertical circular loop which has a 1.2-km radius. What is the magnitude of the resultant force on the 60-kg pilot of this plane at the bottom of this loop? Select the correct answer.
0.98 kN
0.39 kN
1.6 kN
0.54 kN
0.64 kN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

10. A 44-kg child rides on a circus Ferris wheel that takes her around a vertical circular path with a radius of 43 m every 46 s. What is the magnitude of the resultant force on the child at the highest point on this trajectory? Select the correct answer.
35 N
0.47 kN
0.40 kN
0.43 kN
0.95 kN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

11. A race car traveling at 70 m/s enters an unbanked turn of 320 m radius
A race car traveling at 70 m/s enters an unbanked turn of 320 m radius. The coefficient of (static) friction between the tires and the track is 1.3. The track has both an inner and an outer wall. Which statement is correct? Select the correct answer.
The race car will crash into the outer wall.
The race car will crash into the inner wall.
The car will stay in the center of the track.
The car will stay in the center of the track if the driver speeds up.
The car would stay in the center of the track if the radius were reduced to 160 m. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50