Answer:
The computer uses more energy.
Explanation:
We know that the power of an electrical appliance is given by :
[tex]P=\dfrac{E}{t}[/tex]
[tex]E=P\times t[/tex]
E is the energy of the appliance
t is the time taken
For CD player :
Power = 30 watts
Time, t = 3 hours = 10800 s
[tex]E=30\times 10800[/tex]
E = 324000 Joules
or E = 324 kJ
For blender :
Power = 300 watts
Time, t = 2 hours = 120 s
[tex]E=300\times 120[/tex]
E = 36000 Joules
or E = 36 kJ
For hair dryer:
Power = 1500 watts
Time, t = 3 minutes = 180 s
[tex]E=1500\times 180[/tex]
E = 270000 Joules
or E = 270 kJ
For computer:
Power = 200 watts
Time, t = 10 hours= 36000 s
[tex]E=200\times 36000[/tex]
E = 7200000 Joules
or E = 7200 kJ
So, the computer uses more energy i.e. 7200 kJ. Hence, the correct option is (d).
