FOLLOW US ON TWITTER
SHARE THIS PAGE ON FACEBOOK, TWITTER, WHATSAPP ... USING THE BUTTONS ON THE LEFT


YOUR PARTICIPATION FOR THE GROWTH OF PHYSICS REFERENCE BLOG

Thursday, October 23, 2014

Physics 9702 Doubts | Help Page 1

  • Physics 9702 Doubts | Help Page 1




Question 1: [Kinematics > Linear motion]
An aircraft is at rest at one end of a runway which is 2.2km long. The aircraft accelerates along the runway with an acceleration of 2.5ms-2 until it reaches its take-off speed of 75 ms-1. Calculate

(i) the time taken to reach take-off speed
(ii) the distance travelled in this time
(iii) Just as the aircraft reaches take-off speed a warning light turns on. The maximum possible deceleration of the aircraft is 4.0ms-2 and 2.5s elapses before the pilot takes any action, during which times the aircraft continues at its take off speed. Determine whether or not the aircraft can be brought to rest in the remaining length of runway.
Reference: Cambridge International AS and A Level Physics Coursebook – 2nd edition – by David Sang, Graham Jones, Gurinder Chadha and Richards Woodside



Solution 1:
Go to
An aircraft is at rest at one end of a runway which is 2.2 km long.





Question 2: [Current of Electricity > Resistance]


(a) {Detailed explanations for this part of the question is available as Solution 391 at Physics 9702 Doubts | Help Page 72 - http://physics-ref.blogspot.com/2015/02/physics-9702-doubts-help-page-72.html}

(b) Some heaters each labelled 230V, 1.0kW. Heaters have constant resistance. Determine total power dissipation for heaters connected as shown in each diagram below.

Reference: Past Exam Paper - November 2010 Paper 21 Qu6(b)











Question 3: [Deformation of Solids > Young modulus]
Wire of length 1.70 m hangs vertically from fixed point, as shown. Wire has cross-sectional area 5.74 × 10–8 m2 and is made of material that has Young modulus of 1.60 × 1011 Pa. Load of 25.0 N is hung from wire.


(i) Extension of wire
(ii) Same load is hung from second wire of same material. This wire is twice the length but same volume as first wire. Explain how extension of second wire compares with that of first wire

Reference: Past Exam Paper – June 2011 Paper 21 Q4(b)



Solution 3:
Go to
A wire of length 1.70 m hangs vertically from a fixed point, as shown in Fig. 4.1.




Question 4: [Current of Electricity > Variable resistor]
Variable resistor in (a) now connected as potential divider, as shown. Maximum possible and minimum possible current I2 in ammeter:


Reference: Past Exam Paper – June 2011 Paper 21 Q5(b)



Solution 4:









Question 5: [Sound Waves > CRO]
Loudspeaker produces sound wave of constant frequency. How cathode-ray oscilloscope (c.r.o.) may be used to determine frequency:

Reference: Past Exam Paper – November 2010 Paper 23 Q3



Solution 5:
Go to
A loudspeaker produces a sound wave of constant frequency. Outline how a cathode-ray oscilloscope (c.r.o.) may be used to determine this frequency.







Question 6: [Kinematics > Linear motion]
Student takes measurements to determine value for acceleration of free fall. Some of apparatus used is illustrated in Fig. Student measures vertical distance d between base of electromagnet and bench. Time t for iron ball to fall from electromagnet to bench is also measured. Corresponding values of t2 and d are shown.

(a) Draw line of best fit
(b) Explain why there is a non-zero intercept on the graph
(c) Determine student’s value for (i) Diameter of ball            (ii) Acceleration of free fall

Reference: Past Exam Paper – November 2010 Paper 23 Q4



Solution 6:
Go to
A student takes measurements to determine a value for theacceleration of free fall. Some of the apparatus used is illustrated in Fig.4.1.

 




Question 7: [Units]

Cylindrical tube rolling down slope of inclination θ moves distance L in time T. Equation relating these quantities is L (3+a2/P) = QT2sinθ where a is internal radius of tube and P and Q are constants.

Which line gives the correct units for P and Q?



            P                      Q
A         m2                    m2s-2
B         m2                    ms-2
C         m2                    m3s-2
D         m3                    ms-2


Reference: Past Exam Paper – November 2011 Paper 11 Q4 & Paper 13 Q5







Solution 7:

Go to
 

2 comments:

  1. In your answer to question 4(b)(i) why have you given the answer in 2 sf ?

    ReplyDelete
    Replies
    1. it's actually 1 d.p.

      usually we give answers to 3 sf or 1 dp

      Delete

If it's a past exam question, do not include links to the paper. Only the reference.
Comments will only be published after moderation

Currently Viewing: Physics Reference | Physics 9702 Doubts | Help Page 1