A 2.5 kg ball swings in a horizontal circular path at the end of a string. The radius of the circle is 0.6 m and the ball makes 4 revolutions in a second. Calculate the centripetal acceleration of the ball.

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

Acar of mass m goes around a banked curve of radius r with speed v. if the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal force on the car from the road is equal in magnitude to 101) a) mv2/r b) mg/2. d) mg e) tan[v2/(eg)]

Which of the following are forms of phase changes a. freezing b. condensation c. heating d. exchanging