a = ( v(2) - v(1) ) ÷ ( t(2) - t(1) )
2 = ( v(2) - 10 ) ÷ ( 6 - 0 )
2 × 6 = v(2) - 10
v(2) = 12 + 10
v(2) = 22 m/s
Distance = (30+40+50) = 120 km
It's back where it started, so displacement = zero
F = force applied to lift the box = weight of the box = 88 N
P = power produced while lifting the box upward = 72 Watt
v = speed of the box = ?
Speed of the box is given as
v = 
inserting the values
v = 
v = 0.82 ms⁻¹
Answer:
Maximum permitted surface crack length is 1.29 mm
Explanation:
As per the question:
Tensile stress, 
Surface energy of magnesium oxide, SE = 
Modulus of elasticity of the material, E = 225 GPa = 
Now,
To calculate the maximum allowable surface crack length:

