Question

How many calories are equal to one BTU? (One calorie = 4.186 J, one BTU = 1 054 J.)

a. 0.252

b. 3.97

c. 252

d. 397

Answer 1

Step-by-step explanation:

Given

1 calorie is equals to 4.186 J

and 1 BTU equals to 1054 J

using unitary method

`1\ calorie \equiv 4.186 J`

`1\ calorie \equiv 4.186 * 1 J`

and
`1\ J \equiv (1)/(1054) BTU`

thus
`1\ calorie \equiv 4.186 * (1)/(1054) BTU`

`1\ calorie\ \equiv 0.00397 BTU`

`1\ calorie\ \equiv 397\time 10^(-5) BTU`

or
`BTU=251.88\approx 252 cal`

Answer 2

option (c)

Step-by-step explanation:

According to the question

1 BTU = 1054 J

4.186 J = 1 cal

So, 1 J = 1/4.186 cal

So, 1054 J = 1054 / 4.186 cal

= 251.8 cal

By rounding off, it is 252 cal

So, 1 BTU = 252 cal