PAGE 1 OF 14 E-MAIL: MIAMIMATHTUTOR@GMAIL.COM CONTACT NUMBER: (786)556-4839 PHYSICS I NEWTON S LAWS OF MOTION PRACTICE PROBLEMS 5.1 1. If a net horizontal force of 130 N is applied to a person with mass 60.0 kg who is resting on the edge of a swimming pool, what horizontal acceleration is produced? [2.2 m/ ] 2. What magnitude of net force is required to give a 135-kg refrigerator an acceleration of magnitude 1.40 m/. [189 N] 3. A box rests on a frozen pond, which serves as a frictionless horizontal surface. If a fisherman applies a horizontal force with magnitude 48.0 N to the box and produces an acceleration of magnitude 3.00 m/, what is the mass of the box? [16.0 kg]
4. A crate with mass 32.5 kg initially at rest on a warehouse floor is acted on by a net horizontal force of 140 N. What acceleration is produced? How far does the crate travel in 10.0 s? What is its speed at the end of 10.0 s? [4.31 m/, 215 m, 43.1 m/s] PAGE 2 OF 14
5. At the surface of Jupiter s moon Io, the acceleration due to gravity is. A watermelon weights 44.0 N at the surface of the earth. What is the mass on the earth s surface? What are its mass and weight on the surface of Io? [4.49 kg, 4.49 kg, 8.13 N] PAGE 3 OF 14
6. A.22 rifle bullet, traveling at 350 m/s, strikes a block of soft wood, which it penetrates to a depth of 0.130 m. The block of wood is clamped in place and doesn t move. The mass of the bullet is 1.80 g. Assume a constant retarding force. How much time is required for the bullet to stop? What force, in newtons, does the wood exert on the bullet? [ ] PAGE 4 OF 14
PAGE 5 OF 14 7. Given 30.0 N of E 60 S of W and 40 E of S. Find the components of each vector. Find the vector components of the resultant force. Find the magnitude and direction of the resultant force. Express your answer in three different ways. [, or ]
8. Two crates, of mass 75 kg and 110 kg, are in contact and at rest on a horizontal surface. A 730-N force is exerted on the 75-kg crate. If the coefficient of kinetic friction is 0.15, calculate the acceleration of the system, and the force that each crate exerts on the other. [2.5 m/, ] PAGE 6 OF 14
PAGE 7 OF 14 9. A block lies on a smooth plane tilted at an angle to the horizontal. Determine the acceleration of the block as it slides down the plane. If the block starts from rest 9.10 m up the plane from its base, what will be the block s speed when it reaches the bottom of the incline? Ignore friction.
10. If, find the acceleration of block 2. Assume. [3.50 m/ downward] PAGE 8 OF 14
11. Find the tension in each cord if the weight of the suspended object is 490 N. PAGE 9 OF 14
12. Find the tension in each cord if the weight of the suspended object is 490 N. PAGE 10 OF 14
13. 10. If, find the acceleration of block B. Assume. [3.50 m/ downward] PAGE 11 OF 14
PAGE 12 OF 14 14. A child sits on a merry-go-around, 1.5 meters from the center. The merry-go-around is turning at a constant rate, and the child is observed to have a radial acceleration of 2.3 m/. How long does it take for the merry-go-around to make one revolution?
PAGE 13 OF 14 15. John is pulling a sled to haul up a snowy hill to this cabin. The slope is 22.0 from the horizontal, the sled has a mass of 16.0 kg, the coefficient of kinetic friction between the sled runners and the snow is 0.130, and John can exert a force of 1400 N parallel to the surface of the hill. What is the largest load of wood (in kg) that John can take in one trip?
PAGE 14 OF 14 16. Two objects A and B on a perfectly horizontal surface are connected by a light cord. The mass of A is greater than that of B. A horizontal force is applied to Q as shown in the figure below, accelerating the bodies to the right. The magnitude of the force exerted by the connecting cord on body P will be