# Conceptual Physics Final Part 2

### 45 terms by mlobell

#### Study  only

Flashcards Flashcards

Scatter Scatter

Scatter Scatter

## Create a new folder

40 km/hour

### What is the difference between speed and velocity?

Speed- how fast something is going
Velocity- how fast something is going AND its direction

### What is the acceleration of a car that increases its velocity from 0 too 100 km per hour in 5 seconds

20 km per hour/per second

### Galileo performed the following experiments with balls rolling down ramps? Why?

1) Falling Vertically happens too fast
2) He wanted to show that acceleration is constant for each ramp.
3) He wanted to show how the distance fallen depends on the time^2

### What exactly is meant by an object in "free fall".

That only gravity is reacting.

10 m/s

### Which is greater, an acceleration from 25 km/h to 30 km/h or one from 96 km/h to 100km/h if both occur during the same same time interval. Explain.

25-30---- 5
96-100----4

25-30 is a greater acceleration.

### Can automobile with a velocity toward the north simultaneously have an acceleration towards the south. Explain and give real examples.

Yes if it is slowing down. EX. a car.

### Starting from rest, one car accelerates to a speed of 50 km/h, and another car accelerates to a speed of 60 km/h. Which car underwent the greater acceleration? Explain

Neither, we don't know the time.

Mega hertz.

### What does Hz mean? An what are the units of Hz?

Hertz. Vibrations/ per second.

### What are the units of period?

Seconds/per vibration.

330 m/s

### What is the speed of sound in water? metal?

water- x4 metal- x15

a million times

10 centimeters

1 meter

### What are the units of sound intensity?

a. watts/ square meter
b. decibels

### What is the relationship between frequency and pitch?

High frequency= high pitch

### What is the relationship between frequency, wavelength, and wave speed.

Wave speed= wave length x frequency

### What is the relationship between period and frequency.

period= 1/frequency

330 m/s

### A sound has a wave length of 2 meters, what is the frequency of the sound?

330= 2 x frequency
divide by 2

165 Hz

1/4 hertz

MATH
f= 1/ period
1/4

### Why doesn't the frequency of a simple pendulum depend on its mass?

1. Mass creates weight, but mass resists change.

### You clamp one end of a hacksaw blade in a vice and twang the free end. It vibrates. Now repeat, but first put a wade of clay on the free end. a. Does the hack saw blade act like a pendulum?

No because the restoring force is not gravity

### b. In class I said that the vibrating hack saw blade can be better understood if i thought of as something else. I talked about a sport. What is the sport and how does the sport help us understand the hacksaw blade?

Ice Skating is the sport. Rotational Inertia. (draw picture)

### Does the medium in which a wave travels move with the wave? Give an example to support your answer.

No, it is just going up and down. Think of a stick in a pond, not left and right just up and down.

### If the speed of sound depends on its frequency, would you enjoy a concert?

No, high pitches get to your ear sooner than low pitches.

1/60th hertz

3,600 seconds

### Why is lightening seen before thunder is heard?

Light travels fast than sound

### The sine curve at right shows a flute played into a microphone. The graph was created using the software and microphone that I used in class. Draw on the graph below.

Higher pitch- more frequency(make more)
Louder sound- higher amplitude(make them longer)

### When a person throws a ball straight up, in the absence of air resistance, by how much does the speed of the ball increase each second while coming back down? Which takes longer, the time for the ball to go up or the times for the ball to come back down?

a. 10 m/s every second
b. same amount

### Why does a stream of water get narrower as it falls from a faucet? Explain. See picture at right.

Gravity. Water is moving faster that has been falling longer.

### If you drop an object, its acceleration toward the ground is 10 m/s^2. If you throw it downward instead, would its acceleration be greater than 10 m/s^2? Explain.

No, acceleration due to gravity is ALWAYS 10 m/s^2. Gravity doesn't care about speed.

### Referring to the ball/hill figures at right Which one of these hills does the ball roll down in the least amount of time?

B. It is moving faster throughout.

### On which of these hills is the speed of the ball greatest when the ball reaches the bottom of the slope?

The same, all have the same potential energy and the beginning and it goes to kinetic at the bottom.

### On which of these hills is the speed increasing and the acceleration constant? Explain.

A. galileo said a ramp has a constant acceleration

### Be picky and correct your friend who says "in free fall, air resistance is more effective in slowing a feather than a coin."

"Free fall means no air resistance"

### Someone standing at the edge of a cliff throws a ball nearly straight up at a certain speed and another ball nearly straight down with the same initial speed. If air resistance is negligible, which ball will have the greatest speed when it strikes the ground below?

Both balls will hit with the same speed because there are no retarding forces act upon them.

### Referring to the question above, which ball will hit the ground first. Explain.

The one you throw down. obviously.

T | H | V 1. 45
0 0 30 ^ 2. 3
1 25 20 3. 6
2 40 10
3 45 0
4 40 10
5 25 20
6 0 30

### Two balls are released simultaneously from rest at the left and of equal length tracks as shown. Which ball, track a or b, reaches the end of its track first.

B. because of the drop

.

Example: