## Unit Conversion

$\lambda=\frac{h}{p}$

AChoudhry_1L
Posts: 55
Joined: Sat Sep 07, 2019 12:17 am

### Unit Conversion

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
Posts: 85
Joined: Fri Aug 30, 2019 12:16 am

### Re: Unit Conversion

AChoudhry_1L wrote: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
Posts: 87
Joined: Fri Aug 09, 2019 12:16 am

### Re: Unit Conversion

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.