1. A small metal weight is suspended from a spring scale as shown in this illustration

Spring Scale

N

1.0

2.0

3.0

4.0- The spring is measure here at 4.0 N

5.0

6.0

7.0

8.0

9.0

10.0

• What is the gravitational force acting on the weight? Explain.

• What is the net force acting on the weight? Explain.

a) W = -4N,   b)  F_net = 0

Explanation:

The suspended weight of the spring ladder is subjected to two forces: the elastic force of the spring directed downwards and the gravitational force directed downwards.

              - W = 0

             F_{e} = W

             F_{e} = W = 4 N

a) the gravitational force is the weight of the body

             W = -4N

b) as the system is in equilibrium, the net force is zero

             F_net = 0

b. false

explanation:

suppose a rock in free fall is dropped off a cliff. after falling for 5 seconds, its speed would not be 100 m/s.