Question

El. A horizontally directed force of 40 N is used to pull a box a distance of 2.5 m across a tabletop. How much work is done by the 40 - N force?
E2. A woman does 160 J of work to move a table 4 m across the floor. What is the magnitude of the force that the woman applied to the table if this force is applied in the horizontal direction?

E3. A force of 60 N used to push a chair across a room does 300 J of work. How far does the chair move in this process?

E4. A rope applies a horizontal force of 180 N to pull a crate a distance of 2 m across the floor. A frictional force of 120 N opposes this motion.

a. What is the work done by the force applied by the rope?

b. What is the work done by the frictional force?

c. What is the total work done on the crate?​

Answer 1

The same formula of work can be applied to all the questions. The answers are:

E1. 100J

E2. 40N

E3. 5m

E4. a.) 360 J           b.) 240 J               c.) 120 J

El. If a horizontally directed force of 40 N is used to pull a box a distance of 2.5 m across a tabletop. The formula to get the much work that will be done by the 40 - N force will be

Work done = force x distance

Work done = 40 x 2.5

Work done = 100 J

E2. If a woman does 160 J of work to move a table 4 m across the floor. We will use the same formula to calculate the magnitude of the force that the woman applied to the table assuming the force is applied in the horizontal direction.

Work done = force x distance

160 = 4F

F = 160/4

Force F = 40 N

E3. Given that a force of 60 N used to push a chair across a room does 300 J of work. Same formula to get how far the chair move in this process.

Work done = force x distance

300 = 60 x distance

distance = 300/60

Distance = 5 m

Therefore, the chair moved 5m away.

E4. Given that a rope applies a horizontal force of 180 N to pull a crate a distance of 2 m across the floor. And a frictional force of 120 N opposes this motion.

a. The work done by the force applied by the rope can  be found by

W = F x S

W = 180 x 2

W = 360 J

b. What is the work done by the frictional force?

W = $F_{r}$ x s

W = 120 x 2

W = 240 J

c. What is the total work done on the crate?

W = (F - $F_{r}$) x distance

Where  $F_{r}$  = frictional force

Substitute all the parameters

W = (180 - 120) x 2

W = 60 x 2

W = 120 J

Learn more about work here: brainly.com/question/8119756