91.6k views
25 votes
A cup of hot water loses 265 cal

of energy to its surroundings.
How many joules of energy is
this?
[?] joules

User Brianz
by
4.0k points

2 Answers

8 votes

Answer:

1,108.76 joules

Step-by-step explanation:

There are 4.184 joules per calorie

4.184 x 265 = 1,108.76

User Venuktan
by
2.9k points
10 votes

Answer:

-1071 Joules

Step-by-step explanation:

The Joule was introduced as the SI unit for energy in 1925. One calorie is equal to approximately 4.184 joules(J). This is a conversion factor that we can write two ways:

(1cal/4.184J) or (4.184J/1cal)

(265 cal)*(4.184J/1cal) = 1071 J

Since the energy is leaving the system, it should be written with a minus sign: -1071J

User Nivia
by
3.3k points