F

4

60

o

F

3

F

1

F

2

Homework (lesson4)

Problem 1

Two forces F

1

and F

3

of magnitude F

1

= 50N and F

3

= 100N are applied to the block shown in the figure below. Knowing that

the block is in equilibrium, determine the magnitudes of the force F

2

and F

4

.

Solution: F

2

= 57.7N, F

4

= 71.2N

Problem 2

Knowing that the magnitude of both F

1

and F

2

is 100N, determine the tension in the cables connected to A and B.

Solution: T

A

= 42.3N, T

B

= 15.4N

Problem 3

The collar A may slide freely on the horizontal smooth rod. Determine the magnitude of the force F and the reaction R of the
rod on the block when the system is in equilibrium.
Solution: F = 7N rightward, R = 7N downward

Problem 4

Determine the resultant moment about A and B for the given systems of vectors

F

1m

1Kg

1m

A

B

v

1

v

2

v

3

O

B

A

v

3

O

B

A

v

1

v

2

x

y

x

y

60

o

30

o

B

A

F

2

F

1

Problem5

Determine the moment about O of the vector v for the following three problems.

V

V

V

O

z

x

y

1

3

3

O

z

x

y

1

3

3

O

z

x

y

1

3

4

3