A7.0-kg rock is subject to a variable force given by the equation f(x)=6.0n−(2.0n/m)x+(6.0n/m2)x2 if the rock initially is at rest at the origin, find its speed when it has moved 9.0 m.

Which of the following statements does not explicitly describe a transfer of money a. a ball dropped from a heigh hits the ground with a high speed. b. the collision produced in a nuclear reaction heat up the surroundings. c. a plane increases its air speed from 150 mi/hr to 200 mi/hr. d. the electricity from the power socket causes the fan to turn.

•• al and bert are jogging side-by-side on a trail in the woods at a speed of 0.75 m/s. suddenly al sees the end of the trail 35 m ahead and decides to speed up to reach it. he accelerates at a constant rate of 0.50 m/s2, while bert continues on at a constant speed. (a) how long does it take al to reach the end of the trail? (b) once he reaches the end of the trail, he immediately turns around and heads back along the trail with a constant speed of 0.85 m/s. how long does it take him to meet up with bert? (c) how far are they from the end of the trail when they meet?

Which of the following are guidelines to follow for obtaining accurate observations