Physics 1 Term Test

Momentum

Momentum

• quantity of motion that an object has

• “mass in motion”

describes an object's resistance to stopping

mass and velocity

The amount of momentum that an object has is dependent upon two variable

directly proportional

momentum is ___________ to both mass and speed

IMPULSE

a certain amount of force you apply for a certain amount of time to cause a change in momentum.

p=mv

momentum formula

J=ft

impulse formula

IMPULSE-MOMENTUM THEOREM

states that the change in momentum of an object equals the impulse applied to it.

LAW OF CONSERVATION OF MOMENTUM

• In the absence of an external force, the momentum of a system does not change.

LAW OF CONSERVATION OF MOMENTUM

• states when a system of interacting objects is not influenced by outside forces (like friction), the total momentum of the system can not change

• the total momentum of all objects interacting with one another remains constant regardless of the nature of the forces between the objects

the total momentum of a system will stay the same before and after a collision

m1v1= -m2v2

LAW OF CONSERVATION OF MOMENTUM equation

RECOIL

a term that refers to moment when a gun moves backwards after it is shot

uniformly accelerated motion

The motion of an object with constant acceleration is also known as ___________

COLLISIONS

any event in which two or more bodies exert forces on each other in a relatively short time.

equals

In any collision, the total net momentum before the collision ___ the total net momentum after the collision

ELASTIC

When objects collide without being permanently deformed and without generating heat

ELASTIC

• Perfectly ___ collisions almost never occur

• Heat is usually generated with collisions, so energy is transformed out of the system

ELASTIC

• Momentum AND Kinetic energy is conserved

• No permanent deformation, no sound, no friction

• Different direction

INELASTIC

• When colliding objects stick together and travel off as one object

Momentum is conserved, but Kinetic energy is NOT

INELASTIC

• Possible permanent deformation, sound, or friction between objects

• Work done by non-conservative forces

• Same direction

PROJECTILE

neglects air resistant

ONE-DIMENSIONAL MOTION

motion along a straight line or in a single direction

MOTION

a change in position with respect to a reference point.

DISPLACEMENT

the straight-line distance between an object’s initial and final positions, with direction toward the final position

DISTANCE

• the total length of path taken by an object in moving from its initial to final position

SPEED

A measure of how fast an object moves; Rate at which distance is covered; The distance traveled by a moving object per unit time

VELOCITY

includes the speed of an object and the direction of its motion.

ACCELERATION

rate of change of velocity; Because velocity is a vector quantity, a change in velocity can be a change in magnitude, a change in direction, or a change in both magnitude and direction

FREE FALL MOTION

• Objects that fall ONLY due to gravity.

• the state wherein a falling object is free from air resistance and falls under the influence of gravity alone

• Projectile’s downward acceleration when it is on air (-9.8 m/s^2)

• Initial velocity is always 0 m/s

PROJECTILE MOTION

a motion in which an object is thrown near the earth’s surface, and it moves along the curved path under the action of gravity only

PROJECTILE MOTION

Traces a curved (parabolic) line because at the same time that the ball is moving horizontally, it is also moving vertically under the effect of gravity.

PROJECTILE MOTION

Object that is initially thrown into the air and continues to move on its trajectory acted upon by gravity.

HORIZONTAL

one of the components of projectile motion

remains constant

entirely independent

VERTICAL

one of the components of projectile motion

velocity of a projectile changes

Time of Flight

• Time taken by the projectile to cover the entire trajectory

Range

• the horizontal (x) distance traveled by the projectile during entire motion

Trajectory

The parabolic path followed by a projectile in air

Type I

• Horizontal, then vertical; there is an initial velocity

• a rock is thrown horizontally from the top of a cliff 88 m high, with a horizontal speed of 25m/s.

Type II

• Ground -> up -> down

• a golf ball was struck from the first tee at Lunar Golf. It was given a velocity of 50m/s at an angle of 42o to the horizontal. On the moon, the acceleration due to gravity is 1.6m/s2

Type III

• Initial velocity;

• a diver takes off with a speed of 10 m/s from a 5 m high diving board at 30 above the horizontal.

45

best angle to fire to reach the largest distance

zero

Velocity in both highest and lowest points will always be __