1. A man wanted to move a block the size 3m x 3m weighing 80kg. If the coefficient of friction between the block and the ground is 0.27. Which of the following methods should be used? a. Slide along the ground by pushing c. Lift it bodily b. Pull it d. Tip it over 2. The essential condition of equilibrium of a body is a. The algebraic sum of horizontal components of all forces must be zero b. The algebraic sum of vertical components of all forces must be zero c. The algebraic sum of forces about a point must be zero d. All of these 3. In which case would more power be needed? a. In lifting up a weight of 100kg at a constant speed of 3m/s b. In lifting up a weight of 100kg at a velocity 3m/s but accelerating upward 0.5m/s c. In lowering the weight at a constant speed of 3m/s d. In lowering the weight at a velocity of 3m/s and accelaration of 1m/s 4. Kinetic Friction is a. maximum value of frictional force when a body is about to move b. friction between two well lubricated bodies c. friction action when the body is in motion d. friction that keens a body in motion

1. A man wanted to move a block the size 3m x 3m weighing 80kg. If the coefficient of friction between the block and the ground is 0.27. Which of the following methods should be used? a. Slide along the ground by pushing c. Lift it bodily b. Pull it d. Tip it over 2. The essential condition of equilibrium of a body is a. The algebraic sum of horizontal components of all forces must be zero b. The algebraic sum of vertical components of all forces must be zero c. The algebraic sum of forces about a point must be zero d. All of these 3. In which case would more power be needed? a. In lifting up a weight of 100kg at a constant speed of 3m/s b. In lifting up a weight of 100kg at a velocity 3m/s but accelerating upward 0.5m/s c. In lowering the weight at a constant speed of 3m/s d. In lowering the weight at a velocity of 3m/s and accelaration of 1m/s 4. Kinetic Friction is a. maximum value of frictional force when a body is about to move b. friction between two well lubricated bodies c. friction action when the body is in motion d. friction that keens a body in motion

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter5: The Laws Of Motion

Section: Chapter Questions

Problem 5.44P: Two blocks, each of mass m, are hung from the ceiling of an elevator as in Figure P5.43. The...

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