Answer: 96N
Explanation:
To calculate the velocity of the impact On the persons head, we have
h = gt²/2
14 = 9.81t²/2
t² = 28/9.8
t² = 2.86
t = 1.69s
V = u + at
V = 0 + 9.81*1.69
V = 16.58m/s
a(average) = (v1² + v2²) /2Δy
a(average) = 16.58² + 0)/2 * 0.005
a(average) = 274.8964/0.01
a(average) = 27489.64m/s²
Using newton's second law of motion,
F(average) = m * a(average)
F(average) = 0.0035 * 27489.64
F(average) = 96.21N
Therefore the force needed by the acorn to do much damage starts from 96N
Answer:
Explanation:
Given
Cross-sectional area of two areas is


It is filled with oil of density 
mass of car place on Large area 
Suppose a mass of m kg is placed on smaller area
According to pascal law's intensity of pressure is same at every point on Liquid




C standards are based on observable, reproducible natural phenomena.
Answer:
r = 6.5*10^-3 m
Explanation:
I'm assuming you meant to ask the diameters of the disk, if so, here's it
Given
Quantity of charge on electron, Q = 1.4*10^9
Electric field strength, e = 1.9*10^5
q = Q * 1.6*10^-19
q = 2.24*10^-10
E = q/ε(0)A, making A the subject of formula, we have
A = q / [E * ε(0)], where
ε(0) = 8.85*10^-12
A = 2.24*10^-10 / (1.9*10^5 * 8.85*10^-12)
A = 2.24*10^-10 / 1.6815*10^-6
A = 1.33*10^-4 m²
Remember A = πr²
1.33*10^-4 = 3.142 * r²
r² = 1.33*10^-4 / 3.142
r² = 4.23*10^-5
r = 6.5*10^-3 m
You can not determine the speed based on the information given