PHYSICS

A chipmunk named Chip was running towards the rising sun. She covered a distance of 28 meters in 4 seconds. What was her velocity?

7m/s east.

Terminal Velocity

the speed limit of a falling object reached when the forward force of gravity equals the backward force of air resistance resulting in a net force of 0N

Inertia

the tendency of an object to resist a change in its motion

A 10 kg cart has a velocity of 22 m/s west. What is its momentum?

220kgm/s west.

Ferrara was driving her new sports car at a speed of 100 kilometers per hour (km/hr). She drove at a constant speed for 2.5 hours. What was the distance she covered?

250km.

A moose reading Dr. Seuss and a goose drinking juice became loose on a west bound caboose. The train traveled a distance of 100 km in 4 hours before the conductor found a noose to catch the moose and some more juice to lure the goose back to their seats on the caboose. What was the velocity of the caboose?

25km/hr west.

Ecole had 12 km to travel to school. She traveled at a speed of 6 km/hr on her bicycle. How much time did it take her to get to school?

2hrs.

A squirrel named Spaulding chased an alligator named Boots from Los Angeles to San Diego and they ran 140 kilometers in 70 hours. What was their velocity?

2km/hr south.

Noah is riding his skateboard easterly and accelerates from a standstill to 10 meters/second (m/s) in a time of 5 seconds. What is his acceleration?

2m/s^2 east.

Jack ran up a steep hill to Jill's house at a speed of 10 km/hr. It took him 3 hours to get to her house. How far was her house from his house?

30km.

An object has a mass of 20 kg and a momentum of 60 kgm/s up. What is its velocity?

3m/s up.

Mickey and Minnie went to Disneyworld a distance of 5000 km. The plane trip took 3.5 hours. What was the speed of the plane?

Approximately 1428.5km/hr, or simply 5000km/3.5hr.

As Mr. Plezia landed on the now north bound get-away car's roof the burglar gave up immediately. The cars velocity changed from 140 km/hr to a stop in 7 seconds. What was the car's acceleration?

-20km/hr/s.

A 100 kg object was pushed left with a force of 75 Newtons. What is its acceleration?

0.75m/s^2 left.

Scarlet is riding her red bicycle a distance of 30 kilometers (km) and it took her 60 minutes to complete the trip. What was her speed?

1/2km/min.

Buzz Lightyear was traveling at a speed of 100,000 km/hr in his spacecraft. How far did he travel in 3600 seconds?

100000km.

Sandy needed to get to the beach fast which was 6 km from his house. His little sister let him borrow her tricycle and his speed was a blistering 0.5 km/hr. How long did it take him to get to the beach?

12hrs.

Julia and her child decided to visit her favorite pet frog, you guessed it, Froggy in Mississippi and walked for 240 hours at a speed of 8 km/hr. What was the distance to Mississippi?

1920km.

What are the four steps you should take to solve a physics problem?

1: Write down what you are given. 2: Write down what you need. 3: Find a formula that relates step 1 to step 2. 4: Substitute and solve.

A car accelerates southerly from 100 km/hr to 200 km/hr in a time of 5 seconds. What is the car's acceleration?

20/km/hr/s south.

A 10 kg cart accelerating at 20 m/s/s east collides with a concrete wall. How many Newtons of force is the wall subjected to?

200N.

Penn and Gwen were going to Antarctica to study penguins. The distance was 16000 km and they went by canoe from California at a paddling speed of 80 km/day. How long was it before they reached Antarctica?

200days.

Mr. Plezia is using his pogo stick to buy some groceries. He lives in San Diego and must pogo to Los Angeles a distance of 180 km to find just the right kind of snoogle berries. It takes him 9 days to get there. What was Mr. Plezia's velocity?

20km/d N.

What is the velocity of a system with a total momentum of 100kgm/s east and a total mass of 5kg?

20m/s east.

As Mr. Plezia arrived at his home he noticed a burglar coming out of his home and jumping into a get- away car. As Mr. Plezia stood quietly in his yard the burglar in the car sped down the street. Mr. Plezia quickly re-ignited his jet pack and accelerated to 200 km/hr in only 5 seconds into the setting sun. What was Mr. Plezia's acceleration?

40km/hr/s west.

What is the mass of an object that has a velocity of 20 m/s north and a momentum of 80 kgm/s north?

4kg.

Carmen was riding her skateboard to Rigoletto's house to watch the opera. She traveled a distance of 20 km in 4 hours. What was her speed?

5km/hr.

On the way back from Los Angeles Mr. Plezia's pogo stick has a blow out and he has no spare pogo stick. He decides to use emergency plan #1 and opens up his suitcase to remove his jetpack 007. It takes him only 30 minutes to return a distance of 150 km. What was his speed returning to San Diego?

5km/m.

A moving cart has a momentum of 3000 kgm/s left and a mass of 600 kg. What is its velocity?

5m/s left.

A bee named Buzz flying north accelerates from 15 m/s to 25 m/s in 2 seconds. What is the bee's acceleration?

5m/s^2 north.

A force of 90 N is applied to a ball. Its acceleration is 15 m/s/s east. What is the ball's mass?

6kg.

What is the speed falling objects accelerate at on Earth?

9.8 m/s^2 down.

Gravity

A field force of attraction between objects due to their masses. On Earth, the acceleration due to gravity is 9.8m/s^2

Backward Force

A force opposite the direction of an object's motion

Mass

A measure of how much matter is in an object (gram(g) = SI base unit).

Weight

A measure of the force of gravity on an object, measured in Newtons (N)

Reference point

A place or object used for comparison to determine if an object is in motion.

Vector quantity

A quantity that has both direction and magnitude (ex 5m left).

Linear relationship

A relationship that has a straight line when graphed.

Frame of reference

A system for specifying the precise location of objects in space and time.

What is the difference between acceleration and deceleration?

Acceleration is a increase, and deceleration is a decrease.

The change in velocity or direction over a unit of time is called?

Acceleration.

Newton's First Law

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. It is also referred to as the law of inertia.

Motion

An object's change in position relative to a reference point.

Fluid

Any substance that can flow and take the shape of its container.

matter

Anything that has mass and takes up space

What is the difference between average speed and instantaneous speed?

Average speed is the speed overall, whereas instantaneous speed is the speed at any given moment.

What is the formula for time?

Distance/speed.

What is the formula for speed?

Distance/time.

Newton's Third Law

For every action there is an equal and opposite reaction

Newton's Second Law

Force, mass, and acceleration are all related, Their relationship is F=ma

What causes ALL motion?

Force.

Unbalanced Forces

Forces that produce a non-zero net force, which changes an object's motion

Why does friction produce heat?

Friction causes molecules to speed up and have more energy, resulting in more heat.

Friction

Friction is a force that opposes motion between any surfaces that are touching.

What is fluid friction? Give an example.

Friction that acts on objects that are moving through a fluid. For example, when a skydiver dives, he's falling toward Earth with a parachute. Resistance of the air against the parachute slows his descent. The faster or larger a moving object is, the greater is the fluid friction resisting its motion. That's why there is greater air resistance against the parachute than the skydiver's body.

What is static friction? Give an example.

Friction that acts on objects when they are resting on a surface. For example, when you walk, there is static friction between your foot and the floor. Without it, you would fall.

What is rolling friction? Give an example.

Friction that acts on objects when they are rolling over a surface. Rolling friction is much weaker than sliding friction or static friction. This explains why most forms of ground transportation use wheels.

What is sliding friction? Give an example.

Friction that acts on objects when they are sliding over a surface. It is weaker than static friction. That's why it's easier to slide a piece of furniture over the floor after you start it moving than it is to get it moving in the first place.

Why do heavier objects have more friction than lighter ones?

Heavier objects press together with greater force, and this causes greater friction between them.

Unit of velocity

M/s + DIRECTION.

Units of distance

Meters (m).

Unit of speed

Meters per second (m/s).

When an object changes position over a period of time (compared to a reference point) this is called?

Motion.

Is acceleration linear?

No.

Are there any surfaces which are perfectly smooth?

No. All surfaces have some defects, even if they are at the atomic level.

Action force

One of the pair forces described in Newton's Third Law.

Units of pressure

Pascals (Pa or N/m^2).

Forward Force

Push or pull in direction of an object's motion, or to start motion

What is the formula for distance?

Speed * time.

The amount of distance a moving object covers per unit of time is called?

Speed.

What are the four types of friction?

Static, sliding, rolling, and fluid friction.

Pressure

The amount of force exerted per unit area of a surface.

Speed

The distance an object travels per unit of time.

Reaction force

The force that is equal in strength and opposite in direction to the action force, which acts simultaneously on whatever is exerting the action force.

X-axis

The horizontal axis on a coordinate plan where y = 0.

Distance

The length of a path between two points.

What do the length of arrows represent for force?

The length of each arrow represents the strength of the force.

Free Fall

The motion of a falling object when the only force acting on it is gravity.

What is the net force of two opposing forces?

The net force would be the difference in Newtons between the two forces, in the direction of the greater force.

What is the net force of two forces moving in the same direction?

The net force would be the sum of the two forces, in the direction they're both going.

Acceleration

The rate at which velocity changes (uses direction).

Law of Conservation of Momentum

The rule that in the absence of outside forces the total momentum of objects that interact does not change.

Velocity

The speed of an object in a particular direction.

Slope

The steepness of a line on a graph, equal to its vertical change divided by its horizontal change (rise/run).

Net Force

The sum of all forces acting on an object

Y-axis

The vertical axis on a coordinate plane where x = 0.

What is the relationship between force and acceleration?

There is a direct relationship. If force is doubled, then acceleration is doubled.

What is the relationship between mass and acceleration?

There is an inverse relationship. The more the mass, the less the acceleration when force is applied to an object.

impulse

a vector quantity defined as the product of the force acting on the body and the time internal during which the force is exerted

The amount of distance a moving object covers in a particular direction per unit of time is called?

Velocity.

To calculate an object's acceleration, you need to know:

Vf - vi / t + dir (if provided).

Pascal's Principle

When force is applied to a confined fluid, the change in pressure is transmitted equally to all parts of the fluid.

Does acceleration include direction?

Yes.

What is a magic triangle and how do you use it?

You use the magic triangle by covering up the variable you're trying to solve for, and multiplying the variables next to each other, or dividing by the bottom variable. This only works on equations with 3 variables.

What is the formula for acceleration?

a = vf - vi / t + dir.

Force diagram

a diagram showing all the forces acting on an object. When the size and orientation of arrows depict the strength and direction of the forces

Momentum

a property of moving objects that is calculated by multiplying mass x velocity (p=mv). The base unit of the metric system is kgm/s in a direction

air resistance

force that opposes the motion of objects that move through the air

Balanced Forces

forces acting on an object that combine and form a net force of zero, causing no change to motion