<span>a) 3 bulbs rated 40W for 5 hrs : 3*40*5 = 600 Watt hours
</span><span>b) A heater rated 1500W for 3hrs 3* 1500 = 4500 Watt hours
</span>
<span>c) A fridge rated 400W
Would assume the Fridge would run for 24 hours a day :400*24 = 9600 Watt hours
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Total Watt hours for 1 day :
600 + 4500 + 9600 = 14700 Watt hours
Unit of Electricity is in kWh
14 700 wh = 14700/1000 = 14.7kWh
But 1kWh = Rs.3
14.7 kWh = 3*14.7 = 44.1
Total cost = Rs.44.10
35m/s is meters per second.
35x35=1225
it will have gone a total of 1225 meters on thirty five seconds
A Physical Change, alters the form of a substance but does not change the material into another substance.
1500m = 1 sec
9000m/1500 = 6
So, it would take 6 sec to go 9000m
Here, you can derive that by numerical method, as follows:
F = m.a
m = F/a
So, here we can see when we decrease one, other increase by same effect; we can say they are "Indirectly Proportional" to each other!
Hope this helps!