Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

2019 PHYSICS fall > CH3 AND TRIG > Flashcards

CH3 AND TRIG Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What is your favorite class?

A

Physics.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does SOH CAH TOA stand for?

A

sin angle= opp/hyp cos angle = adj/hyp tan angle = opp/adj

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How to solve for x: trig X = B/C

A

UNTRIG: trig-1 (B/C) = x

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How to solve for x: trig A = X/C

A

SLIDE: C trig angle = x

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How to solve for x: trig A = B/X

A

SWITCH: B/trig angle = x

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How to solve triangles when there are no angles given?

A

PYTHAGOREAN THEOREM (or law of sines)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are other names for UN-TRIG?

A

arc trig, inverse trig, trig ^ -1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What to the interior angles of a triangle add up to?

A

180 degrees, since a right triangle already has a 90 degree angle, the other two angles are complementary (add to 90)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do the two smaller angles in a right triangle add up to?

A

90

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What do you call angles that add to 90?

A

Complementary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What angle of elevation will give the same horizontal range as a 20 degree launch?

A

A 70 degree launch. Complementary angles go the same horizontal distance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

sin 70 = cos __

A

20

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

cos 50 = sin __

A

40

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

sin 50 / cos 50 = tan ____

A

50

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

sin m = cos ___

A

90-m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

cos g = sin ____

A

90-g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

sin f / cos f = tan ___

A

f

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How far does a dropped object fall in 1sec, 2sec, 3sec, 4sec, 5sec? hint: use d=5t^2

A

5m, 20m, 45m, 80m, 125m.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Vectors have both _____ and _____

A

magnitude and direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe magnitude and direction.

A

Magnitude answers “how much?” and direction answers “which way?”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is difference between vector and scalar quantities?

A

Vectors have magnitude and direction, so combining them is tricky. Scalars have magnitude only, so they can be easily added, subtracted, multiplied and divided.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Give examples of vector quantities.

A

Velocity, acceleration, and force.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Give examples of scalar quantities.

A

mass, time, volume, area.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

A thrown baseball has has two velocity components. Describe them

A

A vertical component and a horizontal component. The vertical component and the horizontal components are independent, so they do not act on eachother. The vertical changes (accelerates) and the horizontal is constant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Discuss the vertical component of a thrown baseball

A

CHANGING VELOCITY. The vertical component is impacted by gravity, so always changing by 10m/s per second.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Discuss the horizontal component of a thrown baseball.

A

SAME VELOCITY THE WHOLE TIME. Because we ignore air resistance, we assume that the baseball moves at constant velocity horizontally

27
Q

How can you think about the horizontal component of velocity to help understand it?

A

GROUND SHADOW, for Vx, horizontal, imagine the sun straight above and visualize the speed of the shadow cast on the ground. the speed of the shadow is the horizontal speed.

28
Q

How can you think about the vertical component of velocity to help understand it?

A

WALL SHADOW, For Vy, the vertical speed, imagine a huge spotlight behind where the projectile is being launched from, pointing in the direction of the projectiles path. Also imagine a wall just beyond it. the speed of the shadow of the ball on that wall is the vertical speed.

29
Q

If we know the horizontal and vertical component of a thrown baseball, how can we find the initial velocity?

A

Use the PYTHAGOREAN THEOREM v = sqrt (h squared + v squared)

30
Q

If you know horizontal and vertical component, how do you find angle??

A

tan -1 (opp/adj)

31
Q

The vector given is usually the ________ of the triangle.

A

hypotenuse

32
Q

Plane traveling north at 300 km/h hits headwind of 100km/h. What is landspeed? airspeed?

A

landspeed is 200km/h and airspeed is still 300km/h

33
Q

Special triangles?

A

3-4-5 (37-53-90), 1-1- sqrt 2 (45-45-90), 1-sqrt 3- 2 (30-60-90)

34
Q

What are the 3-4-5 right triangle angle measures

A

ABOUT: 37-53-90. (across from those sides respectively)

35
Q

what are the angle measures of a 1-1-root 2 triangle?

A

45 -45- 90 across from those sides respectively)

36
Q

what are the angle measures of the 1- sqrt 3- 2 triangle?

A

30- 60- 90 (across from those sides respectively)

37
Q

What are the side lengths of the 37-53-90 triangle?

A

3, 4 and 5

38
Q

What are the side lengths of the 45-45-90 triangle?

A

1, 1 and sqrt 2

39
Q

What are the side lengths of the 30-60-90 triangle?

A

1, sqrt 3 and 2

40
Q

A plane traveling north at 300 km/h with no wind: What is landspeed?

A

landspeed is 300km/h and airspeed is still 300km/h

41
Q

A plane traveling north at 300 km/h airspeed hits southerly wind of 50 km/h. What is landspeed?

A

250 km/h

42
Q

A plane traveling north at 300 km/h airspeed hits southerly wind of 300 km/h. What is landspeed?

A
  1. It will look like it is standing still in mid-air (like a seagull)
43
Q

A plane traveling north at 300 km/h airspeed hits northerly wind of 50 km/h. What is landspeed?

A

350 km/h. The wind speed adds to groundspeed

44
Q

A plane traveling north at 300 km/h airspeed hits easterly wind of 400 km/h. What is landspeed?

A

Landspeed is the diagonal of triangle with sides 300 and 400, using 3-4-5 triangle, the diagonal is 500km//h. The airspeed is still 300km/h

45
Q

If a bullet is shot horizontally at the exact time another is just dropped from the same height right next to it, which will land first (on flat surface)?

A

they will land at the same time

46
Q

When drawing velocity vectors along the path of a projectile, what doesn’t change?

A

The horizontal vectors don’t change.. horizontal velocity stays constant.

47
Q

When drawing velocity vectors along the path of a projectile, how does the vertical vector change?

A

Gravity impacts it. They become shorter on the way up, and ZERO at top, then get longer on the way down (pointing down) The velocity changes every second (10m/s each second). JUST THE VERTICAL becomes zero, but it is still moving horizontally!

48
Q

what is a “horizontal range?”

A

the distance a projectile travels along the ground (horizontally)

49
Q

What is an interesting fact about horizontal ranges of projectiles and angles aside from 45 is the furthest?

A

Complementary angles (angles that add to 90) have the same horizontal range. EXAMPLE: kicking a ball at 30 degrees will go the same distance as 60 degrees (neglecting air resistance. Shooting an arrow at 10 degrees will travel the same horizontal distance as one shot up at 80 degrees!!!

50
Q

When is a projectile traveling the slowest?

A

At the top. the velocity is ALL HORIZONTAL there because the vert v is zero.

51
Q

Explain why a projectile is traveling slowest at the top

A

We know the horizontal component is always the same, so that will always be contributing, but the vertical component becomes ZERO at the top. The velocity at the top, then, is just the horizontal speed. You can visualize this by imagining a ball thrown straight up.. it stalls at the top for a split second.

52
Q

What is the vertical velocity component of a projectile at the highest point?

A

ZERO

53
Q

What is the horizontal velocity component of a projectile at the top?

A

The same as it is everywhere. The horizontal speed doesn’t change

54
Q

What is the vertical acceleration of a projectile at the highest point?

A

10m/s2. A projectile is accelerating towards earth at 10 meters per second each second along the entire path.

55
Q

What is the horizontal acceleration of a projectile at the top?

A

ZERO. It does not accelerate horizontally, it stays the same speed

56
Q

What is the horizontal acceleration of a projectile as it flies through the air?

A

ZERO. It does not accelerate horizontally, it stays the same speed

57
Q

What angle of elevation maximizes horizontal range?

A

45 degrees.

58
Q

SATELLITES: How much does the earth curve over 8 km?

A

about 5 meters

59
Q

SATELLITES: If an object falls at about 5 m in first second, and the earth curves about 5m every 8km. How fast would something have to travel horizontally to never hit the earth?

A

8km/s (neglecting air resistance)… now you orbit :)

60
Q

SATELLITES: How far up is the international space station?

A

250 miles (400 km) From here to Burlinton VT, at about the canadian border!

61
Q

SATELLITES: How fast does the international space station move?

A

8 km/s . (17,500 mph, about 5 miles per second)

62
Q

SATELLITES: How many times does the international space station orbit the earth each day?

A

It circles the earth every 90 minutes, about 16 times a day!!

63
Q

SATELLITES: Why do we have to be above earth’s atmosphere to orbit?

A

Traveling 5 miles in a second, or 8km/s, air resistance makes it impossible. things would burn up (like shooting stars do)

2019 PHYSICS fall (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions