1. No resultant force . weight component = frictional force
b) Weight comp greater than friction ,
ii) resultant force = ma
iii) 24 N
ci) resultant force = 38 N , a = 3.2 ms-2
ii) v = 0.8 ms-1
d) acceleration
2. a)200g and 100g at 4 cm and 8 cm respectively
b) Summation of force is zero and summation of torque is zero
c) Moment = 0.2 x 9.81x 4x10-2= 0.078 Nm
d) Reaction force = 0.5 x 9.81= 4.9 N
3ai) hdg = 735 000Pa
ii) 8.35 x 105 Pa
b) 1.625 x 106 Pa
c) density of fresh water less than density of salt water
4a) Random path or zig zag path
b) air molecules hit the dust in all direction. Just as likely to be up or down.
c) random movement smaller
5ai) funnel no longer giving heat to ice.
ii) inside the large piece could well be below freezing point.
or better contact between heater and ice
b) mass of beaker and water
ci) Pt = mc@
c=4.9 x 103 Jkg-1K-1
ii) heat lost/gained or impurities in water
7a) show spreading of waves . keep to same wavelength
b) 8 Hz
c) the same
8a) change ac to dc
b) 86400C
c) 12 J of energy delivered for every coulomb of charge
di) series ii) total power - 16W , 1.33 A iii) 57600J
9 a) pump water to a higher level of shortage
b) less heat loss as current is low when transmitted at high voltage.
c) I2R
d) 34900
e) I = 25A
