A skydiver jumps from a flying plane. his height from earth is given through formula h=400+3t-4.9t^2. 1. in which moment the velocity is 46m/s?

2. find the momentum acceleration

Now I've solved it but I'm not sure whether I found it correctly or not.
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An ideal transformer has 60 turns in its primary coil and 360 turns in its secondary coil. if the input rms voltage for the 60-turn coil is 120 v, what is the output rms voltage of the secondary coil?

Which of the following explains why it took so long for the public to accept the negative health effects of smoking? a)people were waiting for counter reasons, and those were presented. b)scientists had not completely finalized their results, which took 30 years. c)cigarettes were cheaply available and media channels were very inefficient. d)cigarette manufacturers were trying hard to bring an alternative into the market

What happens to an isotope during radioactive decay?