Science Vocabulary Sect. 2

Front 1

terminal velocity

Back 1

the constant velocity of a falling object when the force of air resistance is equal in magnitude and opposite in direction to the force of g ravity

Front 2

Electrical force

Back 2

the force of attraction or repulsion on a charged par ticle that is due to an electric field

Front 3

free fall

Back 3

the motion of a body when only the force of g ravity is acting on the body

Front 4

magnetic force

Back 4

the force of attraction or repulsion generated by moving or spinning electric charges

Front 5

air resistance

Back 5

the forces that are in opposition to the relative motion of an object through the air. Drag forces act opposite to the oncoming flow velocity. Drag, unlike other resistive forces, depends directly on velocity.

Front 6

momentum

Back 6

a quantity defined as the product of the mass and velocity of an object

Front 7

Newton's 1st law of motion

Back 7

An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Front 8

balanced force

Back 8

two forces acting in opposite directions on an object, and equal in size. Anytime there is a balanced force on an abject, the object stays still or continues moving continues to move at the same speed and in the same direction.

Front 9

Projectile motion

Back 9

the curved path that an object follows when thrown, launched, or otherwise projected near the surface of Ear th

Front 10

inertia

Back 10

the tendency of an object to resist being moved or, if the object is moving, to resist a change in speed or direction until an outside force acts on the object

Front 11

kinetic friction

Back 11

Kinetic friction, also known as sliding frictionor moving friction, is the amount of retarding force between two objects that are moving relative to each other.

Front 12

Newton's 2nd law of motion

Back 12

The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.

Front 13

static friction

Back 13

the friction between two or more solid objects that are not moving relative to each other. For example, static friction can prevent an object from sliding down a sloped surface. The coefficient of static friction, typically denoted as μs, is usually higher than the coefficient of kinetic friction.

Front 14

unballanced force

Back 14

If two individual forces are of equal magnitude and opposite direction, then the forces are said to be balanced. An object is said to be acted upon by an unbalanced force only when there is an individual force that is not being balanced by aforce of equal magnitude and in the opposite direction.

Front 15

law of universal gravitation

Back 15

Newton's law of gravity states that the gravitational force between two bodies is proportional to the product of their masses and inversely proportional to the square of the distance between them.

Front 16

tensional force

Back 16

the force that is transmitted through a string, rope, cable or wire when it is pulled tight by forces acting from opposite ends. The tension force is directed along the length of the wire and pulls equally on the objects on the opposite ends of the wire.

Front 17

Newton's 3rd law of motion

Back 17

For every action, there is an equal and opposite reaction. The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object.

Front 18

normal force

Back 18

The normal force is the support force exerted upon an object that is in contact with another stable object. For example, if a book is resting upon a surface, then the surface is exerting an upward force upon the book in order to support the weight of the book.

Front 19

contact force

Back 19

In physics, a contact force, is a force that acts at the point of contactbetween two objects, in contrast to body forces. Contact forces are described by Newton's laws of motion, as with all other forces in dynamics. Contact force is the force in which an object comes in contactwith another object.

Front 20

frictional force

Back 20

a force that opposes motion between two sur faces that are in contact

Front 21

gravitational force

Back 21

Newton's law of gravity states that the gravitational force between two bodies is proportional to the product of their masses and inversely proportional to the square of the distance between them.