Question

You can make a smoothie in a blender with a power of 400 watts and an efficiency of 85 percent. How much energy is actually being used to make the smoothie in 30 seconds?A) 8600 JB) 3000 JC) 6580 JD) 10,200 J

Answer 1

In order to calculate the total energy used in 30 seconds, first let's find the power that is actually used, by multiplying the power and the efficiency:

`P=400\cdot(85)/(100)=340\text{ W}`

Now, to find the energy used, let's multiply the power by the amount of time:

`\begin{gathered} E=P\cdot t\\ \\ E=340\cdot30\\ \\ E=10200\text{ J} \end{gathered}`

Therefore the correct option is D.