Unit 1 2010
Question 1
(a)
(i)
5
- +--
4
..i --+r -
---:---i--;-.--.:-
'--i--- -i"'
-i
r
3
2
1
E
0
J
5--:
-1
-2
3
.Y-.,
- --'
-4
13 accurate points
2 mks
< 13 accurate points
1mk
Lines
2 mks
(ii)
1''
tls
Uniform acceleration
Collision Ball rebounds
Ball changes direction and comes to rest
(iii) (a)
v-u
1mk
t
4.2-O:
1
3.5 ms-'
1.2-0
(b)
1mk
1mk
1mk
lmk
Area under line = %b xh
:Yzxl.2x4.2
:2.5m
I mk
1 mk
5
(c)
m(u-u)
| =ma:'t
1mk
:- o.a(-2.+-+.2)
1mk
L.25-7.2
: -91.2 N
(iv)
Inelastic collision
Loses kinetic energy
1mk
1mk
Total 15 marks
Question 2
(a)
(i)
Red
Violet
White
Violet
I rnk
Red
(ii)
Refraction l mk
Red
Correct colour dispersion 1 mk
White
Violet
(iiD
1mk
(b) (i)
01
sin 01
0z
sin 02
31.00
0.s 15
48.3
0.746
41.9
0.667
75.20
0.967
43.6
0.690
90.00
I
Tolerance + 2 in final digit
1 mk for read-off
I mk for calculation
(6 mks)
1mk
Critical angle of glass 43.6o
(ii)
55o > critical angle .'. total intemal reflection
(iii) gradient read off
substitution
answer 1.45 t 0.01
lmk
1mk
1mk
1mk
Total 15 marks
a
Question 3
(a)
(i)
Load
Load
Load
Extension
Extension
Steel wire
GIass
Extension
Polymeric material
(1 mk each)
(ii)
(b)
Stress: force per unit area
lmk
Strain: extension/original length
1 mk
(i)
Extension, ALlm
(ii)
0.012
0.006
0
0.019
0.028
0.050
lmk
0.6
0.5
0.4
.. _.. ---_: _ _.L^-: . ,.
,1---,-.-.. .--i
a!
I
!t(!
0.3
!
o.2
0.1
0
0
0.01
0.02
0.03
extension / m
Axes/Scale 1 mk
6 accurate points 2 mks
(< 6 accurate points) 1 rnk
1 rnk
Line
0.04
0.05
0.05
(iii)
r
E
(iv)
mgL
AAL
lmk
: gradienr (+ )
1mk
0.2-0
..
gradient=#:16.7kgm-l
1mk
0.012 -0
E: gradient (+ )
E_
1.67x 5x1o-2 x9.8 :1.82
3x10-2x 1.5x10-3
(1 mk)
1mk
x 106 Nm-2
(1 mk)
Total 15 marks
Question 4
(a)
(i)
(ii)
(b)
(i)
:0
I rnk
I torque:0
lmk
Tcos26o=W
T=150lcos26o
lmk
lmk
T= 167N
1mk
F:Tsin26o
lmk
F:73 N
1mk
X forces
fJ* : 1.6 cos 20o :1.5 rns-l
Uy: 1.6 sin 20o:0.55 ms'l
lmk
lmk
(iD y: ut +'Aat2
1mk
Y:-2'2m
lmk
-2.2:0.55t- 4.9t2
1mk
t: 0.73 s
lmk
OR
(iiD
time up
x2
time down
1mk
1mk
add
1mk
lmk
x:uxt
: 1.5 x 0.73
1mk
:1.1 m
lmk
Total 15 marks
Question 5
(a)
(i)
Threshold of hearing: Intensity level where a sound becomes audible I mk
Threshold of pain: Intensity level beyond which sounds become unbearable
lmk
(b)
(ii)
Ear responds to a wide range of frequency
(iii)
0
: 10 16910 I
lmk
(iv) 0:10 log,oj4
1.0 x i-o-12
lmk
:96 dB
lmk
lo
lmk
(v)
1 mk
Threshold of hearing increases in intensity
Audible frequency range decreases, especially at high end of frequency
(i)
Waves going towards wall interfere with waves reflected
Minimum occurs where there is destructive interference
Not zero because the reflecting wave has a smaller amplitude
(ii)
Three loops in standing wave so h : 1.5 m
lmk
1mk
lmk
lmk
lmk
f = vllu
:330/1.5
:220 Hz
1 mk
1 mk
OR
Four loops in standing wave so h : 1.125 m
f : vl)"
1 mk
= 330/1.125
(iii)
=293H2
lmk
)":2 m
1 mk
Maximum is at 50 cm from wall
imk
lmk
Total 15 marks
Question 6
(a)
(i)
The e-m waves cause atoms in the cold body to vibrate faster and so get hotter
lmk
(ii)
1 mk
Radiation from the sun passes through the COz
1 mk
It is absorbed at the surface and causes warming
The warmed surface radiates at a longer wavelength than the radiation from the
I mk
sun
This radiation cannot escape because it cannot pass through the greenhouse gases
1mk
(b)
(i)
H--kA- AT
A,X
1 mk (may or may not have the minus sign)
: 80.4 x 4.6 x6+7- q1o
1mk
:277 kW
lmk
4xL0 '
(ii) P= oAQf -rt)
= 5.67 x 10-8 x 4.6 x (9204 - 3034)
: 185 kW
Conversion from
oC
to K
1mk
1mk
lmk
lmk
(tf P = o A If used.... max2out of 4 ...P : 187 kW)
(iiD 185 kW of the power conducted through stove walls from interior is radiated
1 mk
away by the exterior surface
Thus (277 - 185) kW = 92 kW is transferred by convection and conduction into
2 mks
the surrounding
air
Total 15 marks
0