Question

19. A crow-bar of length 20 m is used as a machine to lift a box of 100 kgf by
placing a fulcrum at a distance of 0.1 m from the box. Calculate the effort required
Effort am - 20 m 0.1 m - 19 m​

Answer 1

Answer:

Length of crow bar = 2m

length of load arm = 0.1M

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

=2−0.1=1.9m

so, velocity ratio = length of effort arm/length of load arm = 1.9/0.1 = 19

use formula, velocity ratio = load/effort

19 = 100kgf/effort

effort = 100/19= 5.26 kgf

hence,5.26 effort is required.