A ship is 150m long and has a wetted area of 5000m2. If it is encrusted with barnacles, the ship requires 7000 hp (horsepower) to overcome friction drag when moving in seawater at 15 kn (knots) and 20oC. What is the average roughness of the barnacles

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

A1000-kg weather rocket is launched straight up. the rocket motor provides a constant acceleration for 16-s, then the motor stops. the rocket altitude 20-s after launch is 510-m. you can ignore any effects of air resistance. a. what was the rocket’s acceleration during the first 16-s? b. what is the rocket’s speed as it passes through a cloud 5100-m above the ground?

What causes the formation of ocean currents?