1. Apply the method described in class to construct free-body diagrams for the various situations described below. Answers will be looked at during the next lesson.

1. A book is at rest on a tabletop. Diagram the forces acting on the book.
2. A girl is suspended motionless from a bar which hangs from the ceiling by two ropes. Diagram the forces acting on the girl.
3. An egg is free-falling from a nest in a tree. Neglect air resistance. Diagram the forces acting on the egg as it is falling.
4. A car is coasting to the right and slowing down. Diagram the forces acting upon the car.
5. A rightward force is applied to a book in order to move it across a desk with a rightward acceleration. Consider frictional forces. Neglect air resistance. Diagram the forces acting on the book.

1. Vicky pushes a 8kg crate across the floor with a 24N force directed to the left.
   1. If there is no friction, how fast will the box accelerate?
   2. If there is 8N of friction, how fast will the box accelerate?
   3. How much friction is needed for the box to travel across the floor at a constant speed?

1. A 60 kg skydiver is accelerating at a rate of 2m/s/s.
   1. How strong is the force of air resistance?
   2. If the sky diver experiences an air resistance of 600N, what is the acceleration?
   3. What does that mean for the speed of the sky diver?

1. An elevator starts at the top floor. Alejandro, whose mass is 50kg, gets into the cab and steps on the scale that measures weight in Newtons.

a. What does the scale read before the elevator starts moving?

b. If the scale reads 400N when the elevator starts accelerating down, what is the acceleration?