Answer:
The correct option is;
c. Leaving the chuck key in the drill chuck
Explanation:
A Common safety issues with a drill press leaving the chuck key in the drill chuck
It is required that, before turning the drill press power on, ensure that chuck key is removed from the chuck. A self ejecting chuck key reduces the likelihood of the chuck key being accidentally left in the chuck.
It is also required to ensure that the switch is in the OFF position before turning plugging in the power cable
Be sure that the chuck key is removed from the chuck before turning on the power. Using a self-ejecting chuck key is a good way of insuring that the key is not left in the chuck accidentally. Also to avoid accidental starting, make sure the switch is in the OFF position before plugging in the cord. Always disconnect the drill from the power source when making repairs.
Answer:
874 psi
Explanation:
Given a sample mean (x') = 900,
and a standard error (SE) = 10
At 99% confidence, Z(critical) = 2.58
That gives 99% confidence interval as,
x' ± Z(critical) x SE = 900 ± 2.58 x 10
The value of the lower limit is,
900 - 25.8 = 874.2
≈ 874 psi
Answer:
d=4.63 mm
Explanation:
Given that
Load ,P = 10,100 N
FOS = 1.5
Sy= 900 MPa
Therefore the working stress will be
Lets take the diameter of wire = d mm
The area
For design purpose
A=16.83 mm²
d=4.63 mm
Answer:
The force of friction always acts in a direction, opposite to that in which the body is moving.
The magnitude of kinetic friction bears a constant ratio to the normal reaction between the two surfaces. ...
For moderate speeds, the force of friction remains constant.