Question

A CROW BAR WITH LENGTH 200 CM IS USED TO LIFT A LOAD OF 600N . IF THE DISTANCE BETWEEN FULCRUM AND LOAD IS 0.75. CALCULATE ; a, effort b, MA c, VR

Answer 1

a. Effort = 960 Newton

b. Mechanical advantage (M.A) = 0.625

c. Velocity ratio (V.R) = 1.67

Step-by-step explanation:

Given the following data;

• Load = 600 N
• Length of crowbar = 200 cm
• Length of load arm = 0.75 m

Conversion:

100 cm = 1 m

X cm = 0.75 m

Cross-multiplying, we have;

X = 0.75 * 100 = 75 cm

First of all, we would find the effort arm;

Effort arm = length of crow bar - length of load arm

Effort arm = 200 - 75

Effort arm = 125 cm

Next, we would determine the mechanical advantage (M.A) of the crow bar;

`M.A = \frac {Effort \; arm}{Load \; arm}`

Substituting the values into the formula, we have;

`M.A = \frac {125}{200}`

M.A = 0.625

To find the effort of the crow bar;

`M.A = \frac {Load}{Effort}`

Making "effort" the subject of formula, we have;

`Effort = \frac {Load}{M.A}`

`Effort = \frac {600}{0.625}`

Effort = 960 Newton

Lastly, we would determine the velocity ratio (V.R);

`V.R = \frac {length \; of \; effort \; arm}{length \; of \; load \; arm}`

`V.R = \frac {125}{75}`

V.R = 1.67