An overnight rainstorm has caused a major roadblock. Three massive rocks of mass

Question

An overnight rainstorm has caused a major roadblock. Three massive rocks of mass m1 = 556 kg, m2 = 792 kg and m3 = 388 kg have blocked a busy road. The rocks are side by side blocking the road and lined up from left to right in order as m1, m2 and m3. The city calls a local contractor to use a bulldozer to clear the road. The bulldozer applies a constant force to m1 to slide the rocks off the road. Assuming the road is a flat frictionless surface and the rocks are all in contact, what force, FA, must be applied to m1 to slowly accelerate the group of rocks from the road at 0.400 m/s2?

Fa=????

Use the value found above for FA to find the force, F12, exerted by the first rock of mass 556 kg on the middle rock of 792 kg.

F12=

Explanation / Answer

Three massive rocks of mass m1 = 556 kg, m2 = 792 kg and m3 = 388 kg

the road at a=0.400

The total mass to be moved = 556 + 792 + 388 = 1736 kg.

Force applied to all the blocks (FA) = ma = 1736 * 0.400 = 694.4 Newtons.

The force applied to just the first rock - ma = 556 * 0.400 = 222.4 Newtons.

the first rock of mass 556 kg on the middle rock of 792 kg.

So the remaining force applied to the last two rocks (F12) = 694.4 - 222.4

= 472 Newtons.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.