Ch. 05 Homework

A small car and a large truck have a head-on collision. Which of the following statements is true? A. The magnitudes of both forces are the same. B. Both forces are identical. C. The greater force acts on the car. D. The greater force acts on the truck.

A. The magnitudes of both forces are the same.

How do the vertical and horizontal components of velocity change for a ball tossed at an upward angle? A. The vertical component decreases in magnitude until it reaches the maximum height and then increases; the horizontal component is constant. B. The vertical component is constant; the horizontal component is constant, too. C. The vertical component increases in magnitude until it reaches the maximum height and then decreases; the horizontal component is constant. D. The vertical component decreases in magnitude until it reaches the maximum height and then increases; the horizontal component continuously decreases.

A. The vertical component decreases in magnitude until it reaches the maximum height and then increases; the horizontal component is constant.

How many forces are required for an interaction? A. Two forces, an action and a reaction, are needed for an interaction. B. One force, an action, is needed for an interaction. C. Two forces, a contact force and a friction force, are needed for an interaction. D. One force, a reaction, is needed for an interaction.

A. Two forces, an action and a reaction, are needed for an interaction.

When Monkey Mo dangles by a rope and pulls on his cage, each at different angle from the vertical, the rope tension will be greater than _______. A. both his weight and the pull on his cage B. his weight C. the pull on his cage D. the answer cannot be determined

A. both his weight and the pull on his cage

What is meant by the term vector resolution? A. When a vector is broken into two components parallel to the vector, it is said to experience vector resolution. B. A vector can be broken into two components at right angles that add together to make the original vector. C. When two vectors are subtracted using the parallelogram law, they are said to experience vector resolution. D. When two vectors are added using the parallelogram law, they are said to experience vector resolution.

B. A vector can be broken into two components at right angles that add together to make the original vector.

The force that propels a rocket is that provided by _______. A. ejected fuel B. the expelled gas pushing on the rocket C. energetic reactions as the fuel is burned D. decreased mass

B. the expelled gas pushing on the rocket

State two forms of Newton's third law of motion. Check all that apply. A. Whenever one object exerts a force on a second object, the second object exerts an unequal and identical force on the first. B. For every action there is an opposite reaction. C. For every action there is an equal and opposite reaction. D. Whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first. E. For every action there is an identical reaction. F. For every action there is an unequal and opposite reaction. G. Whenever one object exerts a force on a second object, the second object exerts an equal and identical force on the first. H. Whenever one object exerts a force on a second object, the second object exerts an unequal and opposite force on the first.

C. For every action there is an equal and opposite reaction. D. Whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first.

Fill in the blanks: Newton's first law is often called the law of ____; Newton's second law is the law of ____; and Newton's third law is the law of ____. A. Action, inertia, force B. Acceleration, inertia, action -reaction C. Inertia, acceleration, action -reaction D. Inertia, net force, friction

C. Inertia, acceleration, action -reaction

If we hit a stake with a hammer, we call the force by the hammer the action force. What is the reaction force? A. The reaction force is zero because the force of the hammer on the stake is equal and opposite to the force of the stake on the hammer. B. The reaction force is the force of the hammer on the stake. C. The reaction force is the force by the stake on the hammer. D. The reaction force is the force due to compression inside the stake.

C. The reaction force is the force by the stake on the hammer.

When you push against a wall, what pushes back? A. Nothing pushes back. B. Your fingers push back. C. The wall pushes back. D. Your hand pushes back.

C. The wall pushes back.

Earth pulls down on you with a gravitational force that you call your weight. Do you pull up on Earth with the same amount of force? A. Earth exerts a much greater force on you than you exert on Earth. B. No, the contact force from the ground cancels the force of Earth on you. C. Yes, you pull up on Earth with the same force. D. No, the contact force from the ground cancels the force by you on Earth.

C. Yes, you pull up on Earth with the same force.

A boxer cannot exert much force on a piece of tissue paper suspended in air because _______. A. the time of the interaction is too brief B. there is little follow-through with the punch C. the tissue paper has too little mass to exert much force on the boxer's fist D. the tissue lacks enough strength

C. the tissue paper has too little mass to exert much force on the boxer's fist

Which of Newton's three laws focuses on interactions? A. Newton's second law B. Newton's zeroth law C. Newton's first law D. Newton's third law

D. Newton's third law

Identify the force that propels a rocket. A. The rocket is propelled because the action force of the rocket on the exhaust gases is less than than the reaction force of the exhaust gasses on the rocket. B. The rocket is propelled because the action force of the rocket on the exhaust gases is greater than the reaction force of the exhaust gasses on the rocket. C. The rocket is propelled by the reaction force of the exhaust gasses bouncing off the air molecules outside the rocket. D. The rocket is propelled by the reaction force from the particles accelerated out the rear by an action force from the rocket.

D. The rocket is propelled by the reaction force from the particles accelerated out the rear by an action force from the rocket.

Which of the force diagrams in the figure correctly displays all of the horizontal forces exerted on the cart by the surrounding air?

Diagram A.