It depends on how much time 45 j will go, so if you told me that it went through 45 j per minute it will go through for 2 minutes so not efficient unless it went through 45 j per hour then it is efficient.
Answer:
B
Explanation:
Nonmetals are poor conduster to heat and electricity
Answer:
Explanation:
mg = kx
x = mg/k
x = 30(80)(9.8)/2.8e7 = 0.00084 m ≈ 1 mm
Answer:
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