Chapter 3: Forces & Newton's Laws of Motion
40 N↑, 50 N↓, 30 N←, 30 F→ ^^What is the net force acting on that? a. 10 N down b. 90 N vertical c. 0 N, balanced d. 2 m/s²
a
A feather will fall through the more slowly than a brick because of ______. a. air resistance b. gravity c. inertia d. momentum
a
An object at terminal velocity has an acceleration of _____. a. zero b. 1 g c. 9.8 m/s² d. 98 m/s
a
For any object, the greater the force that's applied to it, the greater its _______ will be. a. acceleration b. gravity c. inertia d. velocity
a
Forces that are equal in size but opposite in direction are _______. a. balanced forces b. frictional forces c. inertial forces d. net forces
a
The product of mass and velocity gives a quantity known as ___. a. momentum b. friction c. inertia d. velocity
a
The sum of all forces acting on an object is the ___ force. a. net b. gravitational c. final d. inertial
a
The upward force↑ on an object falling through the air↓ is ____. a. air resistance b. inertia c. gravity d. terminal velocity
a
When two balls collide, what explains the momentum of the balls after the collision? a. the law of conservation of momentum b. Newton's first law of motion c. Newton's second law of motion d. Newton's third law of motion
a
Whenever a body is in motion, there is always ___ to oppose the motion. a. friction b. inertia c. gravity d. acceleration
a
____ is a force that opposes the motion of objects that move through the air. a. air resistance b. gravity c. static friction d. rolling friction
a
____ is the force that opposes the sliding motion of two surfaces that are touching each other. a. Fricion b. Inertia c. Static d. Gravity
a
A 300-N force acts on 25-kg object. What is the object's acceleration? a. 7500 m/s² b. 300 m/s² c. 25 m/s² d. 12 m/s²
d
A 50.0 kg object has an acceleration of 15 m/s². the force on the object is ____. a. 75.0 N b. 75 N c. 75 kg*m/s d. 750 N
d
Newton's first law of motion states that an object remains at rest unless a(n) ___ force acts on it. a. balanced b. friction c. gravitational d. unbalanced
d
The statement "to action there is an equal and opposite reaction" is ___. a. the law of conservation of momentum b. Newton's first law of motion c. Newton's second law of motion d. Newton's third law of motion
d
When a force is exerted on an object, an equal and opposite force is exerted by the object. What are these forces referred to as? a. centripetal forces b. friction forces c. gravitational forces d. action-reaction forces
d
When the drag force on an object falling through the air equals the force of gravity, the object has reached: a. terminal force b. terminal acceleration c. terminal illness d. terminal velocity
d
When two objects collide, their momentum after the collision is explained by __. a. Newton's first law of motion b. Newton's second law of motion c. Newton's third law of motion d. the conservation of momentum
d
Acceleration due to gravity is ____. a. 98 m/s² b. 9.8 m/s² c. 9.8 m/s d. 0.98 m/s
b
According to New ton's second law of motion, ____. a. F=mv b. F=ma c. F=pv d. F=PA
b
Friction between the tire of a moving car and the dry pavement is ___ friction. a. static b. rolling c. sliding d. riding
b
In the absence of air, a penny and a feather that are dropped from the same height at the same time will____. a. fall at different rates b. fall at the same rate c. float d. not have momentum
b
Inertia varies depending on ____. a. force b. mass c. velocity d. motion
b
The force you have to overcome to start an object moving is ____. a. rolling friction b. static friction c. sliding friction d. air resistance
b
What is Newton's first law also called? a. the law of mass b. the law of inertia c. the law of force d. the law of constant velocity
b
A 3000-N force acts on a 200-kg object. The acceleration of the object is _____. a. 50 m/s² b. 26 m/s c. 15 m/s² d. 150 m/s²
c
A 3000-N force gives an object an acceleration of 15 m/s². What is the mass of the object? a. 45,000 kg b. 1500 kg c. 200 kg d. 15 kg
c
If a 300-N action force is exerted to the right→, the reaction force will be _____. a. 300 N to the right → b. 600 N to the right → c. 300 N to the left ← d. 600 N to the left ←
c
The relationship among mass, force, and acceleration is explained by ________. a. conservation of momentum b. Newton's first law of motion c. Newton's second law motion d. Newton's third law of motion
c
The size of the gravitational force between two objects depends on their ___. a. frictional forces b. inertia c. masses and the distance between them d. speed and direction
c
What kind of force is a car rounding a curve subject? a. rolling b. static c. centripetal d. gravitational
c