Answer:
A real emf device has an internal resistance, but an ideal emf device does not.
E=mcθ
where E is the energy added,m is the mass,c is the specfic heat capacity and θ is the change in temprature.
making m subject u get E/c<span>θ=m
</span><span>θ=(30-20)=10</span><span>
plugging the values we get :
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solving it we get the answer that is 0.25kg or 250 grams
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Yes that's correct. Also zeros in between non-zero numbers are significant figures
<span>the one that should be taken as consideration when describing the quality of a sound is: D.The number of the overtones in the sound
Too many overtones indicated that there is too many unrelated sound that make a lot of the sound's part became redundant and unecessary</span>