Unit Conversion

[AChoudhry_1L]

In homework problem 9 from section 1B, we are given 2 seconds which eventually needs to be converted to joules. The solution manual says that 2 seconds is equal to 64 J. How do we convert seconds to joules?

[Lindsey Chheng 1E]

In homework problem 9 from section 1B, we are given 2 seconds which eventually needs to be converted to joules. The solution manual says that 2 seconds is equal to 64 J. How do we convert seconds to joules?

So in the question we are given 32W, where 1 W = 1 J/s, which means that 32W = 32J/s.
Use dimensional analysis and multiply 32J/s by 2s (amount given in the problem) to end up with the unit of J.

[Letty Liu 2C]

You're not necessarily converting seconds to joules. It's more accounting for the fact that the question asks about two seconds and the energy is in terms of joules per second, which is why you multiply the energy by two.