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(7a)
The minimum energy of the incident ray of thelight must be equal to the work function of thematerial or above the work function of the metal.(7b)(i) polarization.(ii) diffraction.=====================(9)(a)Heat capacity is the quantity of heat required tochange the temperature of a substance by 1 k or1degree Celsius(9b) I. It changes the phase(9d) Given,mass of pepper soup, m=800g=0.800kgInitial temperature of pepper soup,tita =30degree CPower of the microwave oven,P=1200wTime taken, t =3minutes =3*60s =180s.Specific heat capacity of pepper soup,c=4000j/kg k.(9di)final temperature of the pepper soup,@2=? ,Heat given by the microwave oven= Heatabsorbed by the pepper soup.Pt= mc(@2 - @1),1200 * 180= 0.8 * 4000(@2 - 30),216000= 3200(@2 - 30),@2 - 30=67.5 ,@2 = (67.5 + 30)degrees ,@2 = 97.5degree Celsius-------------------------------------------NOTE THAT @ MEANS TITA SIGN.------------------------------------------(9dii) containers with tight-fitting lids are notsuitable for use in microwave cooking becausethere must be room for expansion which can onlybe catered for if the lids are not tight-fitted(9diii) there is dent on the container because thefinal temperature was so large compared to thematerial used in making the container,I.eplastic.and plastics are not very good for suchheat.The cooling of the plastic cannot be uniform.
mass of pepper soup, m=800g
=0.800kg
Initial temprature of pepper soup,
tita =30degree C
Power of the microwave oven,
P=1200w
Time taken, t =3minutes =3*60s =180s.
Specific heat capacity of pepper soup,
c=4000j/kg k.
mass of pepper soup, m=800g
=0.800kg
Initial temperature of pepper soup,
tita =30degree C
Power of the microwave oven,
P=1200w
Time taken, t =3minutes =3*60s =180s.
Specific heat capacity of pepper soup,
c=4000j/kg k.
(9di)final temperature of the pepper
soup,
@2=? ,
Heat given by the microwave oven= Heat
absorbed by the pepper soup.
Pt= mc(@2 - @1),
1200 * 180= 0.8 * 4000(@2 - 30),
216000= 3200(@2 - 30),
@2 - 30=67.5 ,
@2 = (67.5 + 30)degrees ,
@2 = 97.5degree Celsius
-------------------------------------------
NOTE THAT @ MEANS TITA SIGN.
------------------------------------------
(9dii) containers with tight-fitting lids
are not suitable for use in microwave
cooking because there must be room for
expansion which can only be catered for
if the lids are not tight-fitted
(9diii) there is dent on the container
because the final temperature was so
large compared to the material used in
making the container,I.e plastic.and
plastics are not very good for such
heat.The cooling of the plastic cannot be
uniform.

(9d) Given,

(9d) Given,