promotion image of download ymail app
yoyo asked in 科學及數學其他 - 科學 · 1 decade ago

haet/specific capacity

5.Jack takes out a pack of sushi of mass 500g from a 2 C refrigerator, but he

just leaves it on a table.Germs breed so quickly at 22 C that once the sushi

reaches this temperature,it will be unsuitable for eating.If the specific heat

capacity of the sushi is 3kJ kg^-1 C^-1 and it gains heat at at an average rate of 7W at room temperature of 25 C,within what time must Jack eat the sushi after

taking it out of the refrigerator?

Answer:71.4 min

1 Answer

  • 1 decade ago
    Favorite Answer

    When the sushi rises to 22C, total amount of energy it has absorbed will be

    0.5 x (22 - 2) x 3000 = 30000 J

    Thus, time elapsed will be:

    30000/7 = 4286 sec or 71.4 mins

    Source(s): Myself
    • Commenter avatarLogin to reply the answers
Still have questions? Get your answers by asking now.