Ramses College for Girls Second Secondary May, 2017 Physics Final exam Time: 2 hours

Answer 4 questions only of the following (Begin each question in a new page)

Question 1:

A- Mention the scientific term: 1. It is the distance of the vibrating body at any instant from its rest position or its

equilibrium origin. 2. The ability of the medium to refract the light rays when they pass. 3. The space above the mercury inside the tube of mercuric barometer which is

evcuted except from a few of mercury vapour. 4. The mass of a fluid flowing through a certain area in one second.

B- What are the conditions of: 1. Mechanical waves. 2. Laminar flow.

C- Calculate the pressure exerted by an elephant of 3 tons mass, given that its foot has a diameter of 75 cm, compare this to the pressure exerted by a woman of 70 Kg mass using a thin high heel on a man’s shoe of 2 cm2 (g = 10 m/s2)

Question 2:

A- The diagram shows a train of waves 90 cm long and 3 cn from the lowest to the highest point. The time from the beginning to the end is 10 seconds. Calculate: 1. Number of waves in this wave train 2. Wavelength 4. Frequency 3. Amplitude 5. Speed.

B- Give reasons for: 1. The fiber optic is used in the transmission of light. 2. The volume of a gas bubble inside a liquid increases as it rises up.

C- Plot the graph, write the mathematical relation and slope: 1. Refractive index of a thin prism material on Y-axis and angle of deviation on the X-

axis. 2. Liquid pressure at a point inside a liquid (closed container) on Y-axis and heightof

that point from the bottomat the X-axis.

Question 3:

A- Choose the correct answer, giving reasons for your answer: 1. The ratio between the volume rate of flow of fluid at the beginning and the end of

the tube of flow is……… (1:2 – 2:1 – 1:1 – 1:3)

2. Three parallel rays pass through a prism as shown. The yellow ray emerges tangent to the prism side. The yellow and blue rays are ……..(totally reflected – refract pass - without devition – the blue ray only totally reflected)

3. For the hydraulic press containing air bubbles in the liquid used in it, the ratio between the pressure on the small piston to that of the large equals………(1 – more than 1 – less than 1 – zero)

B- Explain the application od density in the field of medicine.

C- A balloon of maximum capacity one liter contaains 950 cm3 at S.T.P. would the balloon burst when the pressure became 74 cm.Hg and temperatute 27o C ?

Question 4:

A- Compare between (In table form) 1. Angular dispersion – dispersive power. (Definition – mathematical rule) 2. Barometer – Manometer. (liquid used – Uses)

B- The average speed of blood through aorta (r1 = 0.7 cm) is 0.33m/s, from which blood goes to 30 major aarteries (r2 = 0.35 cm). 1. Calculate the speed of blood through the arteries. 2. Blood then flows through blood capillaries with velocity slower than that in the

arteries. Explain

Question 5:

A- From the shown diagram: 1. What happens on heating the water? 2. What do you conclude?

B- Mention the scientific idea & use of each of the following: (In a table form) 1. Periscope. 2. Hydraulic press

C- The following table gives values of sin and the corresponding sin where

represents the angle of incidence of light in air and represents the angle of refraction

of light in the medium. Plot the graphical relation between sin on the ordinate

and the corresponding sin on the abscissa from the graph find:

Sin 0 0.35 0.5 0.65 0.77 0.87 0.95 0.99

Sin X 0.23 0.33 0.43 0.51 0.58 0.63 Y

Ramses College for Girls Second Secondary May, 2017 Physics Final exam Model answers

Question 1: A- Mention the scientific term:

1. Displacement 2. Optical density 3. Torcelli vacum 4. Mass flow rate

B- What are the conditions of: 1. Mechanical waves.

A vibrating body

A material medium

A disturbance that propagates

2. Laminar flow.

Liquid fills the tube completely

Flow is non rotational

During any smal interval of time Q in = Q out

Velocity of flow at any point doesn’t slow with time

Flow may be viscous or not according to friction between layers Question 2: A- Give reasons for:

1. As light passes into the fibers it suffers multiple total internal reflection till it emerges at the other end, so light transmits in a curved path without much loss in intensity or energy

2. Bec. as it moves up pressure inside the liquid decreases P α 1

𝑉 , volume increases

B- Plot the graph, write the mathematical relation and

Question 3: A- Choose the correct answer, giving reasons for your answer:

1. 1:1 Because the volume rate of flow is constant along the tube

2. Totally reflected - Because yellow & blue light have shorter wave length than the

red. Refractive index of prism for them is more. Critical angle less.

3. More than 1. Because part of the pressure will be consumed in decreasing the volume of the bubble.

B- Application of density in field of medicine

Blood density indicates the concentration of blood cells. If low than normal indicates anaemia

Urine density indicates the concentration of salts. It is higher than normal in some diseases.

C-

Question 4:

A- Compare between (In table form)

Angular dispersion Dispersive power

Definition The included angle between the emmerged blue and red light rays after emergence from the prism

The ratio between the Angular dispersion between blue and red to the angle of deviation to the middle

Barometer Manometer.

liquid used Mercury Mercury or water

Uses Atmospheric pressure

Height of a mountain

Air density

Pressure of enclosed gas

Difference between enclosed gas pressure and atmospheric pressure.

B-

2. The sum of cross sectional areas of blood capillaries is large. According to

continuity equation V α 1

𝐴

Question 5:

A- Mention the scientific idea & use of each of the following: (In a table form)

Scientific idea Use

Periscope

The light ray changes its path 90 o when it passes through the 1st prism & changes its path again by 90 o when it passes through the 2nd prism.

In submarines to explore objects above the sea level.

Hydraulic press

Pascal’s principle: Pressure applied to a liquid enclosed in a container is transmitted undiminished to every portion in the liquid and the walls of the container.

* Lifting large mass at the large piston by applying small mass on the small piston * Lifting cars at the service station.

B- From the shown diagram:

Ramses College for Girls Second Secondary January, 2017 Physics Final exam Time: 2 hours

Answer 4 questions only of the following (Begin each question in a new page)

Question 1: A- Mention the scientific term:

1- The increase in gas pressure at constant volume per unit pressure at 0 oC for 1 oC rise in temperature.

2- The velocity of a steady flow is inversely proportional to the cross sectional area of the tube through which it flows.

3- The distance between two successive maximum displacements in the positive or negative directions of a wave

4- A pressure applied to a liquid enclosed in a container is transmitted in full to all parts of the liquid as well as the walls of the container.

B- Mention the quantity measured by each of the following units: 1- kg.m-1s-2 2- kg.m-1s-1 3- kg.m-3

C- The pendulum shown moved from (A) to (B) then to (A) again during 0.1 sec.

1- Choose: The motion represents……… (1

4 -

1

2 -

3

4 - 1) oscillation.

2- Find its periodic time & its frequency 3- Find its displacement

Represent the displacement of this motion graphically. 4- Its velocity at (A) & (B).

Question 2: A- Choose the correct answer: (Show your work)

1- The ratio of diameters in a hydraulic press = 9:2, its mechanical advantage = ……………. (9:2 – 2:9 – 20.25 - 81)

2- The radius of a main artery is 4 times greater than a blood capillary, if the artery is branched into 64 capillaries , the velocity of blood through the blood capillary relative to

that hrough the artery is ……… ( 1

16 -

1

4 - 4 times – 16 times)

3- An equilateral triangle triangle of refractive index = 1.732, the least angle of deviation for a ray of light to pass through it = ………. (30 o - 45o - 60 o - 90 o)

B- Explain the following applications: 1- Detecting how well the car battery is charged. 2- The sedimentation rate test in medicine

C- Two glass bulbs A & B of volumes 200 and 500 respectively are connected together by a short thin tube with valve. They contain dry air at pressure of 76 cm Hg at 27oC. The large bulb is heated to 127

oC, then the valve is opppened. The temperature in bulbs A & B become 62 oC and 107 oC respectively. Calculate the pressure in the large bulb before and after the valve opening.

Question 3: A- Plot the graph, Write the relation and find the slope for each:

1- The relation between the volume of a gas under constant pressure on Y-axis and temperature in degrees celcius on the X-axis.

2- The relation between the angle of deviation of a thin prism on the Y-axis and the refractive index of thin prism material (n)

B- What is meant by? 1- Zero kelvin 3- The reading of a manometer = 8 cm Hg. 2- The laminar flow 4- The critical angle of glass = 41o

C- A thin prism of angle 10o and of refractive index 1.5 for red and 1.53 for blue, calculate: 1- The angle of deviation for both red and blue colours 2- The angular size of the prism 3- The dispersive power of the prism

Question 4: A- Compare between: (In a table form)

1- Electromagnetic waves and Mechanical waves. (speed - Definition) 2- Distructive and Constructive interference (path difference – effect) 3- Boyle’s law & pressure law

(Variables – gas constants – Mathematical relation – graphical representation)

B- Water flows at a speed 0.5 m/s through a 4 cm diameter hose. The hose is horizontal. 1- A what is the mass flow rate of water? 2- At what speed does the water pass through a nozzle whose effective diameter is 0.6 cm?

Question 5: (Answer all this question infront of the grah paper) A- Give reasons for:

1- Equal volumes of different gases kept under constant pressure expand equally when heated through the same interval of temperature.

2- The two slits in thomas young experiment the interference fringes become clearer as the distance between the two slits decrease

B- Mention the scientific idea & use of each of the following: (In a table form) 1- Periscope. 2- Endoscope.

C- The following table illustrates the relation between pressure (P) due to a liquid in clossed vessel and the depth (h) at a point.

Depth h cm 5 10 15 20 25

Pressure P bar 5 X 10-3 10 X 10-3 15 X 10-3 20 X 10-3 25 X 10-3

Plot the graph (P) on Y axis and (h) on the X-axis. From the graph find: 1- The slope 2- The pressure at a point 50 cm deep from the surface 3- The density of the liquid (g = 10 m/s2)

Ramses College for Girls Second Secondary January, 2017 Physics Final exam Model answers Question 1: A- Mention the scientific term:

1- Pressure expansion coefficient of gases ½ 2- Continuity equation ½ 3- wave length of transverse wave ½ 4- Pascal’s principle ½

B- Mention the quantity measured by each of the following units: 1½ 1- Coefficient of viscosity 2- Pressure Density

Question 2: A- Choose the correct answer: (Show your work)

1- 20.25 2- 1

4 3- 60 o

B- Explain the following applications: 2 1- Detecting how well the car battery is charged.

When the battery is low : Density of H2SO4 decreases.

When the battery is recharged: SO42- get free from the lead plates, Density increases.

2- The sedimentation rate test in medicine In Rheumatic fever & gout: The RBCs adhere, their volume increases, the sedimentation rate is faster than normal. In Anaemia: The RBCs are broken down, their volume decreases, the sedimentation rate is slower than normal.

Question 3: A- Plot the graph, Write the relation and find the slope for each: 1 each

Vol = Vol)(1 + αv t) OR (Vol )2 (1 + αv t2)

(Vol )1 (1 + αv t1) Slope = αv (Vol )0 αv = Slope (Vol )0

αo = A (n-1)

Slope = A

B- What is meant by? ½ each

1- Zero kelvin: The temperature at which the volume and pressure of an ideal gas disappear

2- The reading of a manometer = 8 cm Hg. The gas pressure is higher than atmospheric pressure by 8 cm Hg

3- The critical angle of glass = 41o A light ray incident by an angle 41o in glass refracts by angle 90 o

4- The laminar flow

It is the flow in which the adjacent layers slide smoothly with respect to each other and the particles of he liquid follow a smooth pass called stream line

Question 4: A- Compare between:

1- Electromagnetic waves Mechanical waves 1

speed high seed Low speed

Definition Wave formed due to vibrating Electric & magnetic field to each other & to propagation direction

Wave formed due to vibration of medium particles

constructive interference Destructive interference 2-

(m + ½) λ (m + ½) λ The path difference

Effect

3- Boyle’s law pressure law

Variables Volume – Pressure - Density Pressure - Temperature

gas constants Mass - Temperature Mass – Volume – Density

Mathematical relation

P1 (Vol )2 P 2 (Vol )1

P1 T1

P2 T1

graphical representation

Question 5: A- Give reasons for:

1- Because all gases have the same volume expansion coefficient under constant pressure

(αv = 1 273⁄ o K-1)

2- Because ∆y = ƛ𝑅

𝑑 ∆y α

1

𝑑

B- Mention the scientific idea & use of each of the following: (In a table form)

Scientific idea Use

1- Periscope.

The light ray changes it path 90 o when it passes through the 1st prism & changes it path again by 90 o when it passes through the 2nd prism.

In submarines to explore objects above the sea level.

2- Endoscope

Total internal reflection Medical diagnosis & surgery

C-