The correct answer is option b, 63.6 kPa
Given,
The diameter of the heel, d=7 cm=0.07 m
The mass of the child, m=25 kg
The pressure is given by the ratio of the force to the area through which the force is applied.
The force applied on the floor by the child is equal to its weight.
Thus the pressure applied on the floor by the child is given by,
Where A is the area of the cross-section of the heel.
On substituting the known values,
Thus the pressure applied on the floor by the heel is 63.6 kPa
Answer:
Explanation:
Work: This can be defined as the product of force and distance. The unit of work is Joules (J). it can be expressed mathematically as
W = F×d
or
W = .................................. Equation 1
Where b = upper limit, a = lower limit, Fx = expression of force.
<em>Given: a = 0 , b = 1.3 m, Fx = 4 + 15.7x - 1.5x²</em>
Substituting these values into equation 1
<em>W = </em>
W = ᵇ[4x + 15.7x²/2-1.5x³/3 +C]ₐ
Work = upper limit - lower limit
Work = ᵃ[4x + 15.7x²/2 - 1.5x³/3 +C] - [4x + 15.7x²/2 + 1.5x³/3 +C]ᵇ............... Equation 2
Substituting the values of a and b into equation 2
Work = [4(1.3) + 15.7(1.3)²/2-1.5(1.3)³/3 + C] - [0 +C]
Work = [5.2 + 26.53 -3.29 + C] - C
Work = 28.44 J
Work done by the force = 28.44 J.