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 toAn 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)
Solution 2:
Go to
Some heaters are each labelled 230 V, 1.0 kW. The heaters have constant resistance.
Go to
Some heaters are each labelled 230 V, 1.0 kW. The heaters have constant resistance.
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.
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
In your answer to question 4(b)(i) why have you given the answer in 2 sf ?
ReplyDeleteit's actually 1 d.p.
Deleteusually we give answers to 3 sf or 1 dp