Which frequency of electromagnetic energy represents the form of energy used by microwave oven
1. IO hertz
2. 10^9 hertz
3. 10^14 hertz
4. 10^25 hertz

Frequency, f = 10⁹ Hz  

Explanation:

Microwave is a type of electromagnetic wave. The frequency of microwaves varies from 1 GHz to 1000 GHz.

Microwave oven is the device that uses microwaves to heat up material inside it. We know that 1 GHz is equal to 10⁹ Hz.

It means that option (2) i.e. 10⁹ Hz represents the form of energy used by microwave oven.

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.

graph slopes whilst gas cools, then it is flat whilst conensation to liquid happens, the coolong liquid then graphs as a slope when it solidifies graph is flat

latent heat