Tension force transmitted through the chains.
40 km/h to in/s
60*60=3600 seconds in an hour
one km is about 0.621 miles
40 km is about 0.621*40=24.84 miles
5280 feet in a mile
12 inches on each foot
5280*12=63360 inches in a mile
63360*24.84=1573862.4 inches in 40km
40 km/h = 40*1573862.4/3600=17487.36 in/s
Answer
given,
mass of crate attached by cable A = 160 Kg
mass of crate attached by cable B = 73 Kg
acceleration of helicopter = 1.4 m/s²
tension in the cable when the move up
F = m (a + g)
tension in cable B
F = 73 x (1.4 + 9.8)
F = 73 x 11.2
F = 817.6 N
tension in cable A
F = (160 + 73 ) x (1.4 + 9.8)
F = 233 x 11.2
F = 2609.6 N