Bishops - Physical Sciences / Grade 11 / P1 Nov 2008 9

BISHOPS

Diocesan College

November 2008

Grade 11 – Physical Science

Paper 1 - Physics

MARKS: 150 Examiner: K Kruger

TIME: 2 hours Moderator: D Ledwidge

INSTRUCTIONS AND INFORMATION

1.
2.
3.
4.
5.
6.
7.
8.
9. / Write your name in the appropriate space on the ANSWER SHEET and ANSWER BOOK.
Answer ALL the questions.
Answer SECTION A on the attached ANSWER SHEET.
Answer SECTION B in the ANSWER BOOK.
Non-programmable calculators may be used.
Appropriate mathematical instruments may be used.
Number the answers correctly according to the numbering system used in this question paper.
Data sheets are attached for your use.
Give brief motivations, discussions, et cetera where required.

SECTION A

Answer this section on the attached ANSWER SHEET.

QUESTION 1: ONE-WORD ITEMS

Give ONE word/term for EACH of the following descriptions. Write only the word/term next to the question number (1.1 – 1.5) on the attached ANSWER SHEET.
1.1
1.2
1.3
1.4
1.5 / Rate of change of displacement
Product of force and time (that the force acts)
Region of space in which an electrostatic force is experienced
Device to measure quantity of charge flowing per second
Force between two surfaces (sliding over each other) that opposes the motion / (1)
(1)
(1)
(1)
(1)
[5]

QUESTION 2: MATCHING ITEMS

Choose an item from COLUMN B that matches a description in COLUMN A. Write only the letter (A – J) next to the question number (2.1 – 2.5) on the attached ANSWER SHEET.
COLUMN A
/
COLUMN B
2.1
2.2
2.3
2.4
2.5 / The force per unit charge
Quantity with magnitude only
Tendency to continue with state of rest or state of uniform motion
Type of force acting between two electrons
Component of a battery / A
B
C
D
E
F
G
H
I
J / electrostatic
galvanometer
vector
time
inertia
cell
impulse
electric field strength
resistor
electric field / [5]

QUESTION 3: TRUE/FALSE ITEMS

Indicate whether the following statements are TRUE or FALSE. Choose the answer and write 'true' or 'false' next to the question number (3.1 – 3.5) on the attached ANSWER SHEET. Correct the statement if it is FALSE.
3.1
3.2
3.3
3.4
3.5 / When a ticker timer is used in any experiment, the distance between the dots increases.
The change of momentum of a cricket ball being hit by a bat will decrease if time of contact decreases (assume the force of the bat stays constant).
When two capacitors are connected in series, their combined capacitance is equal to the sum of the individual capacitance’s.
The combined resistance of resistors connects in parallel will always be less than the smallest resistor.
According to Newton’s Universal Law of Gravitation, the force between two masses is directly proportional to the square of the distance between them. / (2)
(2)
(2)
(2)
(2)
[10]

QUESTION 4: MULTIPLE-CHOICE QUESTIONS

Four possible options are provided as answers to the following questions. Each question has only ONE correct answer. Choose the answer and make a cross (X) in the block (A – D) next to the question number (4.1 – 4.5) on the attached ANSWER SHEET.
4.1 / Consider the following block being pulled at constant velocity, by a force F applied at 30o to the horizontal.

The coefficient of friction would be
A F /(5 x 9,8)
B (F x Cos 30o )/(5)
C (F x Sin 30o )/(5 x 9,8)
D (F x Cos 30o )/(5 x 9,8) / (3)
4.2 / Which of the following statements concerning momentum is incorrect?
A
B
C
D / Momentum is only conserved in perfectly elastic collisions.
Momentum is measured in kg.m.s-1.
Momentum is the product of the mass of an object and its velocity.
Momentum is a vector quantity. / (3)
4.3 / If a kettle is rated at 2 kW, then it can transfer
A
B
C
D / 2000 Joules of electrical energy in one minute
1000 Joules of electrical energy in 30 seconds
2000 Joules of energy in 1 second
2 Joules of energy in 1 second / (3)
4.4 / Two identical metal spheres on insulated stands carry charges of -Q and 3Q respectively, as indicated in the diagram. When they are at a distance r from each other, they experience a force F.
The two spheres are now touched and then moved apart so that the final distance between them is half the original distance, as illustrated. Which ONE of the following correctly describes the new magnitude of the force that the spheres experience?
A
B
C
D / 4/3 F
3/4 F
2 F
4 F / (3)
4.5 / Consider the following ticker tape:

Which graph represents the motion?
/ (3)
[15]
TOTAL SECTION A: / 35

SECTION B

INSTRUCTIONS AND INFORMATION

1.
2.
3. / Answer SECTION B in the ANSWER BOOK.
The formulae and substitutions must be shown in ALL calculations.
Round off your answers to TWO decimal places.

QUESTION 5

An aircraft needs to fly from town A to town B. B is due East from A and the towns are 250 km apart. A wind blows from the South at a speed of 60 km.h-1 when the pilot leaves.
5.1 / Calculate the resultant speed that the aircraft must fly at (in km.h-1) if it must take 45 minutes to complete the journey / (3)
5.2 / Draw a neat sketch of the relevant vectors and then determine the actual velocity the aircraft must fly, to achieve the resultant speed in Question 5.1. If you wish to determine the resultant velocity by drawing, use a scale of 1cm to 30 km.h-1. / (8)
5.3 / On a different journey, the aircraft flies at 350 km.h-1 on a bearing of 240o. Draw a neat sketch to show the South and West components of this velocity and then calculate these components / (7)
[18]

QUESTION 6 - Newtons Laws and momentum

6.1 / State Newtons second law of motion / (4)
6.2
6.3
6.4
6.5
6.6 / What force is required to accelerate a 1500 kg car at 3 m.s-2? Assume that there are no friction or retarding forces acting.
Calculate the force required to accelerate the above car at 3 m.s-2 if there are retarding forces present which amount to 2000 N?
The above car is used in a Brainiac experiment to test safety devices. The car is travelling at 15 m.s-1 when it collides head on with a 500 kg test cart travelling towards the car at 5 m.s-1. After the collision, the car travels at 5 m.s-1 in its original direction. Calculate the final velocity of the test cart.
If the contact time during the collision was 0,1 s, calculate the force applied on the car.
Name two safety features in a modern car that help protect the driver and explain how they reduce injuries. / (4)
(2)
(8)
(5)
(4)
[27]

QUESTION 7

7.1
7.2
7.3
7.4 / Draw a sketch diagram showing all the forces acting on a ball that is falling through air at terminal velocity.
Consider an astronaut of mass 120 kg, standing on the moon (mass 7,2 x 1022 kg and radius 1,741 x 106 m). Determine the force of attraction by the moon on the man.
Using Newtons second law and the answer from Question 7.2, calculate the acceleration due to gravity on the moon.
Express your answer to Question 7.3 as a fraction of the gravitational attraction on earth. / (3)
(5)
(3)
(2)
[13]

QUESTION 8

Two small spheres are suspended from threads 30 mm apart. The spheres carry a positive charges of 2 x 10-6 C and 4 x 10-6 C respectively.
8.1
8.2 / State Coulombs Law of electrostatics.
How many electrons were removed to give the one sphere its charge of 2 x 10-6 C? / (4)
(2)
8.3 / Calculate the force between the two spheres. / (4)
[10]

QUESTION 9

9.1 / Draw the electric field pattern between the two parallel plates used in a Millikan experiment. Draw the plates as they would be found in the experiment. / (3)
9.2 / In an experiment, what will the magnitude of Electric Field Strength be if 3000 V is applied across the plates when they are 10 mm apart? / (4)
9.3 / Calculate the electrostatic force on an oil drop which has a mass of
4,8 x 10 -15 kg. / (4)
9.4 / Show that the charge on the drop is 1,6 x 10-19 C. / (4)
9.5 / Calculate the work done in moving this charge from one plate to the other. / (4)
[19]

QUESTION 10

A capacitor is a component that is said to store electric charge (and energy).
10.1 / What is misleading about the statement ‘…to store charge’? Limit your comments to charge, not energy. / (2)
10.2
10.3
10.4 / The electronic flash attachment for a camera has a capicitator of capacitance 1000 μF, connected to a 350 V battery,
How much charge can the capacitor hold?
If the dielectric constant of the aluminium oxide used in the capacitor is 9,1 and the plates are situated 0,02 mm, determine the area of the plates.
How is such an area of plate accommodated in an electronic flash unit? / (3)
(5)
(2)
[12]

QUESTION 11

Consider the following electric circuit which has a battery of emf 12 V and an internal resistance r.
11.1 / Calculate the effective resistance of the three external resistors in the circuit. / (4)
11.2
11.3 / If the reading on the ammeter is 0,6 A, calculate the readings on:
a)  voltmeter V1, and
b)  voltmeter V2
Would the lost volts increase, decrease or stay the same if the 2 Ω resistor was removed? Explain. / (8)
(4)
[16]
TOTAL SECTION B:
GRAND TOTAL: / 115
150

Bishops - Physical Sciences / Grade 11 / P1 Nov 2008 9

DATA FOR PHYSICAL SCIENCES P1 GRADE 12

TABLE 1: PHYSICAL CONSTANTS

NAME / SYMBOL / VALUE
Acceleration due to gravity / g / 9,8 m·s-2
Speed of light in a vacuum / c / 3,0 x 108 m·s-1
Planck's constant / h / 6,63 x 10-34 J·s
Gravitational constant / G / 6,67 x 10-11 N·m2·kg-2
Coulomb's constant / k / 9,0 x 109 N·m2·C-2
Charge on electron / e- / -1,6 x 10-19 C
Electron mass / me / 9,11 x 10-31 kg
Permittivity of free space / / 8,85 x 10-12 F·m-1
Permeability of free space / / 4 x 10-7 T·m·A-1

Physical Sciences/P1 3 DoE/Exemplar 2008

NSC

TABLE 2: FORMULAE

MOTION

/ or
or / or

FORCE

WORK, ENERGY AND POWER

/ U

WAVES, LIGHT AND SOUND

or / or
/ or or
/ sin

MATTER AND MATERIALS

/ Stress
Strain

Physical Sciences/P1 3 DoE/Exemplar 2008

NSC

ELECTRICITY AND MAGNETISM

and /
= BA /

ELECTROSTATICS

C = / C =
C = εr

ELECTRIC CIRCUITS

Physical Sciences/P1 DoE/Exemplar 2008

NSC

NAME:

FOR EXAMINER ONLY:

Question / Topic / Total
1 – 4 / Short questions / /35
5 / Vectors / /18
6 / Newtons laws, momentum / /27
7 / Gravitation / /13
8 / Electrostatics / /10
9 / Millikans / /19
10 / Capacitance / /12
11 / Electricity / /16
Total / /150
Percentage / %

ANSWER SHEET

Physical Sciences/P1 DoE/Exemplar 2008

NSC

QUESTION 1

1.1 / (1)
1.2 / (1)
1.3 / (1)
1.4 / (1)
1.5 / (1)
[5]

QUESTION 2

2.1 / (1)
2.2 / (1)
2.3 / (1)
2.4 / (1)
2.5 / (1)
[5]

PTO

Physical Sciences/P1 DoE/Exemplar 2008

NSC

QUESTION 3

3.1
3.2
3.3
3.4
3.5 /
/ (2)
(2)
(2)
(2)
(2)
[10]

QUESTION 4

4.1 / A / B / C / D
4.2 / A / B / C / D
4.3 / A / B / C / D
4.4 / A / B / C / D
4.5 / A / B / C / D
(5 x 3) [15] Total SECTION A: /35