Physics Exam Review

Question 1

What are the rules for significant digits?

Answer 1

If there is a decimal point leading 0s are insignificant
If there isn’t a decimal 0s to the right are insignificant
All other digits are significant

Question 2

What are the rules for significant digits when multiplying and dividing ?

Answer 2

Round your final answer to the least # of significant fig

Question 3

What are the rules for significant digits when adding and subtracting?

Answer 3

Round the final answer to the least accurate # of decimal places.

Question 4

What is a scalar quantity?

Answer 4

Has magnitude but no direction

Question 5

What is a vector quantity?

Answer 5

Has magnitude and direction

Question 6

How do you add vectors in 2 dimensions?

Answer 6

Option 1: Scale diagram. Option 2: Trig.

Question 7

How do you find the average speed/ velocity?

Answer 7

Speed= distance/time. Velocity= displacement/time.

Question 8

How to find instantaneous velocity?

Answer 8

Use the slope. M= change in y/change in x

Question 9

What is mass?

Answer 9

The quantity of matter in an object

Question 10

What is weight?

Answer 10

The force of gravity on an object.

Question 11

What is inertia?

Answer 11

The property of matter that resists change to its motion. The greater the mass the greater the inertia.

Question 12

What is Newton’s first law?

Answer 12

If the net force is 0 it will remain at rest or remain in motion at a constant velocity.

Question 13

What is newton’s 2nd law?

Answer 13

If the net external force is not 0 the object will accelerate in the direction of the net force.

Question 14

What is Newton’s 3rd law?

Answer 14

For every action force there is a reactionary force of = magnitude and opposite direction.

Question 15

What is static friction?

Answer 15

Acts on a stationary object and prevents motion.

Question 16

What is kinetic friction?

Answer 16

Acts to oppose the motion of a moving object.

Question 17

What is the coefficient of friction?

Answer 17

The ratio of the magnitude force of friction to the magnitude of the normal force.

Question 18

What is work?

Answer 18

Is the energy transferred to an object by applied force for a measured distance. J=Nm

Question 19

What is mechanical energy?

Answer 19

The sum of the Eg and Ek for an object.

Question 20

What is percent efficiency?

Answer 20

The ratio of useful output to total energy input.

Question 21

What is power?

Answer 21

The rate work is done or energy is transferred. 1J/s=1W

Question 22

What is transverse vibration?

Answer 22

Object vibrates perpendicular to its axis. (swing)

Question 23

What is longitudinal vibration?

Answer 23

Object vibrates parallel to the axis. (baby jumper)

Question 24

What is torsional vibration?

Answer 24

Twists back and forth around its axis.

Question 25

What is Amplitude?

Answer 25

(A) Distance from equilibrium position to max displacement

Question 26

What is Frequency?

Answer 26

(f) # of cycles completed per unit time. f= #cyc/total t

Question 27

What is Period?

Answer 27

(T) Time to complete one full cycle. T= total t/#cyc

Question 28

State the principle of Superposition

Answer 28

At any point in the medium the resulting amplitude is the algebraic sum of the two interfering amplitudes.

Question 29

What does a reflected pulse from a free end look like?

Answer 29

reflected

Question 30

What does a reflected pulse from a fixed end look like?

Answer 30

reflected and inverted

Question 31

Define Wave

Answer 31

A periodic disturbance which transfers energy over a distance

Question 32

What are the characteristics of a wave?

Answer 32

Crest: The region where the displacement is positive Trough: The region where the displacement is negative Amplitude (A): The distance above/below its equilibrium position to max displacement Wavelength (λ): The distance between any consecutive points on the waves which are in phase (crest-crest)

Question 33

Does amplitude of a pulse affect its speed?

Answer 33

No

Question 34

What happens to wavelength if frequency of vibrations is increased?

Answer 34

As frequency increases, wavelength decreases.

Question 35

Doppler effect

Answer 35

Moving towards = shorter λ, (Vw/Vw-Vs), fd > fs Moving away = longer λ, (Vw/Vw+Vs), fd Vw-speed of wave, V/f s-source speed/frequency

Question 36

Resonance in open air columns | and closed air columns

Answer 36

O: 1st resonant length = 1/2λ, 2nd = 1λ, 3rd = 3/2λ C: 1st resonant length = 1/4λ, 2nd r.l. = 3/4λ, 3rd r.l. = 5/4λ

Question 37

What would happen to the force experienced by two objects if one mass was doubled?

Answer 37

The force would double.

Question 38

What would happen to the force experienced by two objects if both masses were doubled?

Answer 38

Force would be 4x as big.

Question 39

What would happen to the force experienced by two objects if the distance between them was doubled?

Answer 39

Force would be 1/4 as big

Question 40

What would happen to the force experienced by two objects if the distance between was halved?

Answer 40

Force would be 4x as big

Question 41

What is Specific Latent Heat of Fusion?

Answer 41

Amount of therm energy required to melt | Lf=Qf/m

Question 42

What is Specific Latent Heat of Vaporization?

Answer 42

Amount of therm energy required to vaporize (per kg) of a substance at boiling point

Question 43

Specific Latent Heat Equation for Q?

Answer 43

Q(f/v) = mL(f/v)

Question 44

Transverse Waves

Answer 44

When particles vibrate perpendicular to the direction of the wave

Question 45

Longitudinal Waves

Answer 45

Particles vibrate parallel to the direction of propagation of the wave. Extensions are rarefactions, and compressions...

Question 46

Force of attraction between charges

Answer 46

Fe = kQ1Q2 / d^2

Question 47

Find charge if deficit/excess

Answer 47

q = ne

Question 48

What is Induced Fission?

Answer 48

Nucleus struck with free neutron becomes unstable and splits

Question 49

What is Spontaneous Fission?

Answer 49

Unstable heavy isotope splits without interaction

Question 50

What is an atomic mass unit (amu)?

Answer 50

1/12th the mass of carbon-12 mucleus

Question 51

Alpha Particle

Answer 51

Helium nucleus

Question 52

What is Proper Nuclear Notation?

Answer 52

Atomic# on bottom, total# of particles in nucleus on top

Question 53

How to find speed of sound?

Answer 53

v=331.6+0.606t

Question 54

Half life finding t or h

Answer 54

find a common base or log

Question 55

Position Time Graphs

Answer 55

Shows distance over time with respect to reference point. To find velocity use slope. To find acceleration use tangent method.

Question 56

Velocity Time Graphs

Answer 56

Shows velocity over time. To find displacement use area under graph. To find acceleration use slope.