Answer:
229,098.96 J
Explanation:
mass of water (m) = 456 g = 0.456 kg
initial temperature (T) = 25 degrees
final temperature (t) = - 10 degrees
specific heat of ice = 2090 J/kg
latent heat of fusion =33.5 x 10^(4) J/kg
specific heat of water = 4186 J/kg
for the water to be converted to ice it must undergo three stages:
- the water must cool from 25 degrees to 0 degrees, and the heat removed would be Q = m x specific heat of water x change in temp
Q = 0.456 x 4186 x (25 - (-10)) = 66808.56 J
- the water must freeze at 0 degrees, and the heat removed would be Q = m x specific heat of fusion x change in temp
Q = 0.456 x 33.5 x 10^(4) = 152760 J
- the water must cool further to -10 degrees from 0 degrees, and the heat removed would be Q = m x specific heat of ice x change in temp
Q = 0.456 x 2090 x (0 - (-10)) = 9530.4 J
The quantity of heat removed from all three stages would be added to get the total heat removed.
Q total = 66,808.56 + 152,760 + 9,530.4 = 229,098.96 J
Answer:
If an object has a fast velocity, the dots on a ticker tape diagram will be far apart.
120 km/3 hours. 40/1=?/3 1x3=3 hours so 40x3=120 km
Answer:
162 KJ
Explanation:
The electrical energy can be calculated using the formula
E = V×I×t
Where, V= voltage = 120 V
I is current in ampere = 7.5 A and t is time in seconds
1 hour = 3600 sec
Therefore, 0.05 hour = 3600×0.05 = 180 sec
Substitute the values in above equation find electrical power
E = 120×7.5×180
= 162000 J
= 162 KJ
Therefore, the electrical energy use of the microwave = 162 KJ
