Answer:
probability P = 0.32
Explanation:
this is incomplete question
i found complete A manufactures makes integrated circuits that each have a resistance layer with a target thickness of 200 units. A circuit won't work well if this thickness varies too much from the target value. These thickness measurements are approximately normally distributed with a mean of 200 units and a standard deviation of 12 units. A random sample of 17 measurements is selected for a quality inspection. We can assume that the measurements in the sample are independent. What is the probability that the mean thickness in these 16 measurements x is farther than 3 units away from the target value?
solution
we know that Standard error is expess as
Standard error = 
Standard error =
Standard error = 3
so here we get Z value for 3 units away are from mean are
mean = -1 and + 1
so here
probability P will be
probability P = P( z < -1 or z > 1)
probability P = 0.1587 + 0.1587
probability P = 0.3174
probability P = 0.32
Answer:
a) 49.95 watts
b) The self locking condition is satisfied
Explanation:
Given data
weight of the square-thread power screw ( w ) = 100 kg = 1000 N
diameter (d) = 20 mm ,
pitch (p) = 2 mm
friction coefficient of steel parts ( f ) = 0.1
Gravity constant ( g ) = 10 N/kg
Rotation of electric power screwdrivers = 300 rpm
A ) Determine the power needed to raise to the basket board
first we have to calculate T
T = Wtan (∝ + Ф ) *
------------- equation 1
Dm = d - 0.5 ( 2) = 19mm
Tan ∝ =
where L = 2*2 = 4
hence ∝ = 3.83⁰
given f = 0.1 , Tan Ф = 0.1. hence Ф = 5.71⁰
insert all the values into equation 1
T = 1.59 Nm
Determine the power needed using this equation
= 
= 49.95 watts
B) checking if the self-locking condition of the power screw is satisfied
Ф > ∝ hence it is self locking condition is satisfied
Answer:
810 g
Explanation:
Mass is the product of density and volume:
m = ρV
m = (8.1 g/cm³)(100 cm³) = 810 g
The mass of the chunk is 810 grams.