When the wagon's brakes are off, the engine pulls the wagon forwards. A
frictional force also acts on the wagon. In what direction does the frictional
force act?

Which of the following is true about an object in free fall? its acceleration depends on its mass. it has no inertia. it pulls on earth, and earth pulls on it. its momentum is constant.

The rigid beam is supported by the three suspender bars. bars ab and ef are made of aluminum and bar cd is made of steel. if each bar has a cross-sectional area of 450 mm2, determine the maximum value of p if the allowable stress is (σallow)st = 200 mpa for the steel and ( σallow)al = 150 mpa for the aluminum. est = 200 gpa and eal = 70 gpa.

Iwill give 30 points to whoever answers ! what is the formula for actual mechanical advantage and ideal mechanical advantage?