Physics Things to Know Flashcards

1
Q

How do you determine instantaneous velocity from a position-time graph?

A

Slope at a given time

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

How do you determine instantaneous velocity from a velocity-time graph?

A

Value at the given time

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

A block is in equilibrium. What is the Newton’s third law force pair to the normal force?

A

The force the block puts on the surface

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

What is the same for resistors in parallel?

A

Voltage drop

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

What is the equivalent resistance of two 50 ohm resistors in parallel?

A

25 ohms

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

What is the more common word for the “magnitude of the velocity vector?”

A

Speed

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

Write the impulse-momentum theorem.

A

FΔt = Δp

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

State the formula for the angular momentum of a point object.

A

L = mrv

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

State the formula for the angular momentum of an extended object, like a disk or a sphere.

A

L = Iω

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

A 1 kg object moves at 2 m/s. Can this object collide and experience MORE that 2 N᛫s of impulse?

A

Yes

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

What property of a circuit involved the number of electrons passing a position in 1 s?

A

Current

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

John exerts a 4 N force to the left on a cart; Peggy exerts a 3 N force to the right on the cart. Which way is the cart moving?

A

Can’t be determined

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

What physical property of a wave relates to the energy carried by the wave?

A

Amplitude

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

Under what conditions can you set up forces equal to down forces?

A

Equilibrium (a = 0)

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

Equation for energy stored by a spring.

A

PE = 1/2 kx²

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

A 1 kg wooden crate and a 2 kg wooden crate are separately dragged across the floor. What quantity must be the same for both crates?

A

Friction (μ)

17
Q

Write the equation for the electrical force between two point charges.

A

F = (kq1q2) / r²

18
Q

Two massive objects each have a net negative charge. When they are placed near one another, do they attract or repel electrostatically?

19
Q

Write the equation for the period of a pendulum.

A

T = 2π √(l/g)

20
Q

Write two versions of the equation for electrical power.

A
P = IV
P = I²R
P = V² / R
21
Q

Wire 1 is 20 cm long and made out of aluminum. Wire 2 is 40 cm long, of the same cross sectional area, and also made out of aluminum. How many times larger is the resistivity of wire 2 compared to wire 1?

A

Resistivity is the same.

22
Q

The amplitude of an antinode on a standing wave on a string is 2 cm; the period of the wave is 4 s. What is the average speed of the string at the position of the antinode?

23
Q

Draw a representation of the longest-wavelength standing wave that can exist in a pipe which is open at one end and closed at the other end.

A

Half a wave

24
Q

A planet’s orbit about a sun is elliptical. Consider a system consisting of just the planet. Is the planet’s angular momentum about the sun conserved?

25
An object is hung from a spring scale, which reads 2.0 N. Dividing by 10, it's determined that the object's mass is 0.2 kg. Which kind of mass was determined?
Gravitational Mass
26
An object is attached to a horizontal spring, compressing the spring by 0.15 m. A second object, twice as massive as the first, compressed the same spring by 0.15 m. By how much has the potential energy of the spring-object system changed?
None | 1/2kx²
27
A 10 N block is on a surface is which the static friction coefficient is 0.2. The force of friction on the block is 1 N. How is this possible?
F (static friction) ≤ μ (static) F (normal)
28
Identify the error: "Ball A was thrown at a speed of 30 m/s at an angle of 20° above the horizontal. Since its acceleration is 10 m/s², its speed after 3 s will be zero."
Acceleration is in the vertical direction. Only Ball A will have a non-zero speed.
29
Why is it wrong to say "the kinetic energy of the hanging block is downward?"
Energy is secular with no direction
30
Define an "elastic" collision.
No loss of kinetic energy; object bounces perfectly