Un An aircraft travelling at 600 km/h accelerates steadily at 10 km/h per second. Taking the
speed of sound as 1100 km/h at the aircraft's altitude, how long will it take to reach the
Sound barrier'?

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

The consumption of fossil fuels could be

If a substance is in the gas phase, which of qualities of the gas will stay constant? a: volume b: mass c: shape d: position of particles