Problems on Application of Newton's Laws
College Physics, 2e (Knight)
Chapter 5 Applying Newton's Laws
5.1 Quantitative
1) A fish is to be weighed at the harbor. If the mass of the fish is 69.0 kg, what will be the reading on the scale? (Use g = 9.8 m/s2.)
A) 676 N
B) 7.04 N
C) 7.74 N
D) 744 N
Answer: A
Var: 50+
2) A skydiver reaches a "terminal velocity" of 120 km/h. If the skydiver has a mass of 59.0 kg, what is the magnitude of the upward force on the skydiver due to wind resistance?
(Use g = 9.8 m/s2.)
A) 578 N
B) 6.02 N
C) 5.42 N
D) 636 N
Answer: A
Var: 50+
3) A person with a mass of 78 kg is riding in an elevator that is accelerating upward at 1.80 m/s2. What is the person's apparent weight? (Use g = 9.8 m/s2.)
A) 900 N
B) 760 N
C) 620 N
D) 960 N
Answer: A
Var: 35
4) A 80 N force is needed to slide a 50.0 kg box across a flat surface at a constant velocity. What is the coefficient of kinetic friction between the box and the floor? (Use g = 9.8 m/s2.)
A) 0.16
B) 0.13
C) 0.15
D) 0.18
Answer: A
Var: 50+
5) A piano mover raises a 100 kg piano at a constant rate using a frictionless pulley system, as shown in the figure. With roughly what force is the mover pulling down on the rope?
[pic]
A) 2000 N
B) 1000 N
C) 500 N
D) 250 N
E) Depends on the velocity!
Answer: C
Var: 1
6) An object at rest on an inclined plane starts to slide when the incline angle is increased to 17°. What is the coefficient of static friction between the object and the incline? (Use g = 9.8 m/s2.)
A) 0.31
B) 0.27
C) 0.33
D) 0.37
Answer: A
Var: 31
7) A 6.0 kg box slides down an inclined plane that makes an angle of 39° with the horizontal. If the coefficient of kinetic friction is 0.19, at what rate does the box accelerate down the slope? (Use g = 9.8 m/s2.)
A) 4.7 m/s2
B) 5.2 m/s2
C) 5.5 m/s2
D) 6.2 m/s2
Answer: A
Var: 50+
8) Starting from rest, a 75 kg skier slides down a 17.0° slope. If the coefficient of kinetic friction between the skis and
Chapter 5 Applying Newton's Laws
5.1 Quantitative
1) A fish is to be weighed at the harbor. If the mass of the fish is 69.0 kg, what will be the reading on the scale? (Use g = 9.8 m/s2.)
A) 676 N
B) 7.04 N
C) 7.74 N
D) 744 N
Answer: A
Var: 50+
2) A skydiver reaches a "terminal velocity" of 120 km/h. If the skydiver has a mass of 59.0 kg, what is the magnitude of the upward force on the skydiver due to wind resistance?
(Use g = 9.8 m/s2.)
A) 578 N
B) 6.02 N
C) 5.42 N
D) 636 N
Answer: A
Var: 50+
3) A person with a mass of 78 kg is riding in an elevator that is accelerating upward at 1.80 m/s2. What is the person's apparent weight? (Use g = 9.8 m/s2.)
A) 900 N
B) 760 N
C) 620 N
D) 960 N
Answer: A
Var: 35
4) A 80 N force is needed to slide a 50.0 kg box across a flat surface at a constant velocity. What is the coefficient of kinetic friction between the box and the floor? (Use g = 9.8 m/s2.)
A) 0.16
B) 0.13
C) 0.15
D) 0.18
Answer: A
Var: 50+
5) A piano mover raises a 100 kg piano at a constant rate using a frictionless pulley system, as shown in the figure. With roughly what force is the mover pulling down on the rope?
[pic]
A) 2000 N
B) 1000 N
C) 500 N
D) 250 N
E) Depends on the velocity!
Answer: C
Var: 1
6) An object at rest on an inclined plane starts to slide when the incline angle is increased to 17°. What is the coefficient of static friction between the object and the incline? (Use g = 9.8 m/s2.)
A) 0.31
B) 0.27
C) 0.33
D) 0.37
Answer: A
Var: 31
7) A 6.0 kg box slides down an inclined plane that makes an angle of 39° with the horizontal. If the coefficient of kinetic friction is 0.19, at what rate does the box accelerate down the slope? (Use g = 9.8 m/s2.)
A) 4.7 m/s2
B) 5.2 m/s2
C) 5.5 m/s2
D) 6.2 m/s2
Answer: A
Var: 50+
8) Starting from rest, a 75 kg skier slides down a 17.0° slope. If the coefficient of kinetic friction between the skis and