Physics

We cannot see energy with our eyes, but we can observe its effects. Simulations such as [fill in the blank] understand processes that we cannot directly see.

An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?

Define the following terms:

i. Pitch

ii. Sound

iii. Echoes

i. State four (4) characteristics of electromagnetic waves.

ii. Give four (4) characteristics of sound waves.

Which of the following does not affect the electrical resistance of a body?

A) Material composing the body

B) Bodies directly surrounding the body

C) Length of the body

D) Temperature of the body

Which of the following accurately describes circuits?

A) In a series circuit, the current can flow through only one path from start to finish.

B) In a parallel circuit, there's only one path for the current to travel.

C) In a parallel circuit, the same amount of current flows through each part of the circuit.

D) In a series circuit, the amount of current passing through each part of the circuit may vary.

The Chishimba falls is around 20 m high. Water falling from the falls is used for generating electric energy. If 450 m³ of water falls per hour and 50% of the gravitational potential energy can be converted into electric energy, how many 100 W lamps can be lit?

Which statement(s) correctly compare the masses of protons, neutrons, and electrons? Select two options.



A. Protons and neutrons have similar mass.

B. Protons and electrons have similar mass.

C. Neutrons and electrons have similar mass.

D. Protons are smaller than a neutron or an electron.

E. Neutrons are smaller than a proton or an electron.

F. Electrons are smaller than a proton or a neutron.

A proton is a very tiny particle inside an atom. The mass of a proton is estimated to be 0.0000000000000000000000167 g. What is the mass of a proton in scientific notation?

A. $167 \times 10^{-26} g$

B. $1.67 \times 10^{24} g$

C. $1.67 \times 10^{-24} g$

D. $16.7 \times 10^{-25} g$

Calculate the theoretical value of acceleration (c.f., Figure 3 in the “M2 – Description” file).



Measure the distance between the two outside legs supporting the track (use the ruler on the track to measure this value).







l =1.435 ( m )



The height of the aluminum block under one of the legs: Δh = 5.08 cm = 0.0508 m

The operation of nuclear power plants in the United States is closely monitored and regulated.

Please select the best answer from the choices provided.

A. True

B. False

The loudness, L, measured in decibels (Db), of a sound intensity, I, measured in watts per square meter, is defined [tex]L-10 \log \frac{l}{f_0}[/tex], where [tex]f_0=10^{-12}[/tex] and is the least intense sound a human ear can hear. What is the approximate loudness of a dinner conversation with a sound intensity of [tex]10^{-7}[/tex]?

Which of the following statements about nuclear energy is true?

a. Nuclear energy cannot be contained nor controlled.

b. Nuclear energy is contained in nuclear bonds.

c. Nuclear energy is less efficient than other energy forms.

d. All of the above are true.

the bottom of the track consists of a horizontal section L=15m with friction. determine the coefficient of kinetic friction between the block and the bottom portion of the track if the block just makes it to point B before coming to rest

The gravitational force between two objects is 100 N. If the mass of each object is doubled, what is the gravitational force between the objects at the same distance?

A. 25 N

B. 50 N

C. 200 N

D. 400 N

Sort the following quantities by whether they have increased or decreased over cosmic time:



Items:

density of the Universe

temperature of the Universe

size of the Universe

Electromagnetic radiation with short wavelengths and high frequency have what type of energy?

(A) less

(B) more

(C) magnetic

(D) kinetic

What is the radiation that exits from the x-ray tube head?

A. leakage

B. primary

C. scatter

D. secondary

Which statement describes Newton's law of universal gravitation?

A. Mass has little effect on gravity between objects.

B. Gravity pushes objects away from Earth's center.

C. Gravity does not act between Earth and the moon.

D. Every object in the universe attracts every other object.

Which pair of factors affects the force of gravity between objects?

A. direction and distance

B. mass and distance

C. mass and shape

D. shape and time

Which best illustrates the way in which radiation transfers thermal energy?

In addition to how much force Earth exerts on the object, which features of an object affect its weight?

A. mass and location of the object

B. shape and location of the object

C. location of the object and how much energy the object has

D. mass of the object and how much energy the object has

The _____ is an abbreviation for the radiation dose to which body tissues are exposed, which is measured in terms of its estimated biological effects.

A. Sievert

B. Roentgen

C. Gray

D. milliroentgen

The acceleration due to gravity is the constant of variation. What is the acceleration due to gravity of a falling object?

Which of the following is NOT a characteristic of high energy wavelengths?

A. high frequency

B. low penetrating power

C. high penetrating power

D. short wavelength

In addition to x-rays, other forms of electromagnetic energy include which of the following?

A. radio waves

B. television waves

C. visible light

D. all of the above

Which best describes the shape of a convection current?

A. linear

B. spiral

C. circular

D. wave

Which contains the particles that are vibrating fastest?

A. boiling water

B. frozen water

C. room-temperature water

D. cold tap water

Most thermal conductors are made of which material?

A. plastic

B. glass

C. rubber

D. metal

Luminescence is the emission of light that is not caused by heat. A luminescent substance decays according to the function below.



[tex]$I=I_0 e^{3\left(-\frac{t}{0.6}\right)}$[/tex]



This function can be best approximated by

(1) [tex]$I=I_0 e^{\left(-\frac{t}{0.18}\right) I}$[/tex]

(3) [tex]$I=I_0(0.0067)^t$[/tex]

(2) [tex]$I=I_0 e^{5 t}$[/tex]

(4) [tex]$I=I_0(0.0497)^{0.6 t}$[/tex]

1. The dimensions of the ratio 'angular momentum/linear momentum' are,
   
   (1) T
   
   (2) [tex]$M ^{-1} L^{-1}$[/tex]
   
   (3) L
   
   (4) [tex]$L ^{-1}$[/tex]
   
   (5) Dimensionless.
   
2. Which of the following could be the units of gravitational potential?
   
   (A) [tex]$Jkg ^{-1}$[/tex]
   
   (B) V
   
   (C) [tex]$m ^2 s^{-2}$[/tex]
   
   (D) [tex]$Wskg ^{-1}$[/tex]
   
   (1) A only.
   
   (2) B only.
   
   (3) A, B only
   
   (4) A, C and D only
   
   (5) A, B and C, D
   
3. Which of the following instruments can be used to measure a 1 cm length with a percentage error less than [tex]$2 \%$[/tex] ?
   
   
   
   A-A meter rule
   
   B - A vernier scale with a least count of 0.5 mm
   
   C - Micrometer screw gauge
   
   (1) B
   
   (2) C
   
   (3) B,C
   
   (4) A, B, C
   
   (5) None of the above is possible
   
4. In the circuit shown below, the cells and resistances are not shown, and only the currents are marked. What is the current represented by I?
   
   (1) 0.5 A
   
   (2) 1 A
   
   (3) 1.5 A
   
   (4) 2 A
   
   (5) 3 A
   
5. The angles of deviation of two light rays incident on a prism at angles of incidence of [tex]$28^{\circ}$[/tex] and [tex]$47^{\circ}$[/tex] are both [tex]$25^{\circ}$[/tex]. The angle of the prism is,
   
   (1) [tex]$30^{\circ}$[/tex]
   
   (2) [tex]$45^0$[/tex]
   
   (3) [tex]$50^{\circ}$[/tex]
   
   (4) [tex]$60^{\circ}$[/tex]
   
   (5) [tex]$90^{\circ}$[/tex]
   
6. A flywheel has a kinetic energy of 150 J . If a constant torque of 5 Nm is applied in the opposite direction, after how many revolutions will it come to rest?
   
   (1) 1
   
   (2) 3
   
   (3) 5
   
   (4) 6
   
   (5) 9

The table lists the time it takes for an amount of charge to pass through a point in a wire.



| Current | Charge (C) | Time (s) |

|---|---|---|

| W | 18 | 4.3 |

| X | 10 | 3.2 |

| Y | 15 | 3.3 |

| Z | 12 | 3.1 |



Janelle is exploring the relationship between the brightness of a light bulb and the current that powers it. When applying these currents to the same bulb, the bulb is brighter when the current is greater.



Which lists the currents in the order of the bulb brightness they cause from most bright to least bright?



A. W, Y, X, Z

B. Y, W, Z, X

C. W, Y, Z, X

D. X, Z, W, Y

A power source of 2.0 V is attached to the ends of a capacitor. The capacitance is [tex]$4.0 \mu F$[/tex]

What is the amount of charge stored in this capacitor?

A. [tex]$2.0 \mu C$[/tex]

B. [tex]$8.0 \mu C$[/tex]

C. [tex]$6.0 \mu C$[/tex]

D. [tex]$0.50 \mu C$[/tex]

1. State and explain Ohm's Law and represent it mathematically and graphically.
   
2. Define the heating effect of electric current with factors on which the resistance depends.
   
   Numerical Based:

Define heating effect of electric current with factors on which resistance of a wire depends.

Jasmine makes a note card about series circuits. She records the points shown.



\begin{tabular}{|l|l|}

\hline Advantages & Disadvantages \

\hline (1) They are simple to design and build & \begin{tabular}{l}

(2) Each source of current used adds more current to the circuit. \

(3) The more bulbs are added, the dimmer the bulbs are. \

(4) If one bulb goes out, all bulbs go out.

\end{tabular} \

\hline

\end{tabular}



Which change will correct the error on her note card?

A. switching the headings on the columns

B. moving point (4) into the Advantages column

C. moving point (2) into the Advantages column

D. adding the title Parallel Circuits

Define the following terms:

a) One Ampere

b) One volt

c) One coulomb

d) One watt

Define 1 kWh. What is the value in joules?

Compare the advantages and disadvantages of the two methods of storing energy. Include calculations in your answer.

\begin{tabular}{|l|l|l|l|}

\hline \multicolumn{4}{|c|}{Table 7} \

\hline Method & Energy stored per 100 kg of water in kJ & Percentage of stored energy wasted & ln 3 / 35 \

\hline A: Increasing water temperature by $80^{\circ} C$ & 33600 & 40\% & Anywhere \

\hline B: Pumping water uphill to a height of 500 m & 490 & 25\% & High mountains \

\hline

\end{tabular}

Explain the significance of the following features of common liquids in a thermometer:

i. the thin walled bulk

ii. a very fine bore

iii. thick walled stem with a bulge in glass down one side

What is the main difference between protons and neutrons?



A. Protons have a much smaller mass than neutrons.

B. Protons have a much larger volume than neutrons.

C. Protons have an electrical charge, but neutrons have no charge.

D. Protons make up the nucleus, but neutrons orbit around the nucleus.

Use this chart showing the different specific heat of various materials to answer the questions.





| Material | Specific Heat ($J / g ^{\circ} C$) |

| -------- | ---------------------------------- |

| aluminum | 0.90 |

| iron | 0.44 |

| lead | 0.16 |

| sand | 0.83 |

| steel | 0.49 |

| wood | 1.80 |

| water | 4.18 |



Which material has the highest specific heat?

Which material has the lowest specific heat?

Which material has the ability to absorb twice as much heat as aluminum when placed in the same environment of mass and temperature?

1. The distance [tex]$s$[/tex], time [tex]$t$[/tex] and acceleration [tex]$a$[/tex] are related according to the valid equation:
   
   [tex]$s=x t+\frac{a}{y}$[/tex]
   
   
   
   Find the dimension and unit of [tex]$x$[/tex] and [tex]$y$[/tex].

Drag each tile to the correct box. Not all tiles will be used.



Andy is working on an experiment. He places a prism in front of a beam of sunlight. The beam splits into many colors. What sequence does he observe from top to bottom?