Question

A box of mass 400 kg rest on a carrier of truck that moving at speed 120km/hr the driver was applied brake and slows to a speed 60km/hr in 20 second the constant acceleration generated upon the box

Answer 1

mass = 400 kg

u = 120 km/h

v = 60km/h

t= 20 sec

so,

v = u + at

60 = 120 + a * 20

60 - 120 = 20 a

-60. = 20 a

-60/20. = a

so,

a = -3m/s²