Question

MECHANICAL ADVANTAGE PRACTICE PROBLEMS Lever What is the ideal mechanical advantage of a lever with a resistance arm of 3 m and an effort arm of 12 m? 2. You use a lever to lift a filing cabinet to get a lost key. The effort arm is 2 ft and the resistance arm is 1 ft. What is the MAP of the lever? 3. resistance length is 4 cm. Find the MAP of the crowbar. You apply a force on a crowbar to open a stuck door. The effort length of the crowbar is 26 cm long and the 4. A worker uses a board that is 4 m long to pry up a boulder. A small rock is used for a fulcrum and is placed 0.5 m from the resistance end of a lever. Calculate the MA of the board. 5. Three of your friends are all sitting on one end of a seesaw. The combined weight is 275 N. The length from the fulcrum to your friends is 2.5 m. The rest of the seesaw (from the fulcrum to you) is 4.5 m. What is the MA? What effort force is needed to lift your friends? to the board. What is the mechanical advantage of the lever? To pry a wooden board off of a tree house, you can apply a force of 50 N to a lever. The lever applies a force of the MA.

Answer 1

Answer:

1. MA = 4

2. MA = 2

3. MA = 6.5

4. MA = 7

5. MA = 1.8

Effort = 152.78 N

Weight = 90 N

Explanation:

The mechanical advantage of a lever is given as:

Mechanical Advantage = MA = Effort Arm/Resistance Arm

1.

MA = 12 m/3 m

MA = 4

2.

MA = 2 ft/1 ft

MA = 2

3.

MA = 26 cm/ 4 cm

MA = 6.5

4.

Since the resistance arm is 0.5 m and the total board length is 4 m.

Therefore:

Effort Arm = 4 m - 0.5 m = 3.5 m

MA = 3.5 m/0.5 m

MA = 7

5.

Effort Arm = 4.5 m

Resistance Arm = 2.5 m

MA = 4.5 m/2.5 m

MA = 1.8

Another formula for mechanical advantage is:

MA = Weight/Effort

here,

Weight = 275 N

Effort = ?

Therefore,

1.8 = 275 N/ Effort

Effort = 275 N/1.8

Effort = 152.78 N

To lift a wooden board a 50 N force is applied. Therefore,

1.8 = Weight/50 N

Weight = 50 N * 1.8

Weight = 90 N