The reason why giant stars become planetary nebulas is Supergiant stars do not have enough mass to generate the gravity necessary to cause a planetary nebula.
<h3>Why do giant stars become planetary nebulae?</h3>
A planetary nebula is known to be formed or created by a dying star. A red giant is known to be unstable and thus emit pulses of gas that is said to form a sphere around the dying star and thus they are said to be ionized by the ultraviolet radiation that the star is known to releases.
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Answer:
1. High friction
2. High extrusion temperature
Explanation:
Surface cracking on extruded products are defects or breakage on the surface of the extruded parts. Such cracks are inter granular.
Surface cracking defects arises from very high work piece temperature that develops cracks on the surface of the work piece. Surface cracking appears when the extrusion speed is very high, that results in high strain rates and generates heat.
Other factors include very high friction that contributes to surface cracking an d chilling of the surface of high temperature billets.
Answer:
Machine Safeguards must meet these minimum general requirements: Prevent contact: The safeguard must prevent hands, arms, or any other part of a worker's body from making contact with dangerous moving parts. Be secure: Workers should not be able to easily remove or tamper with the safeguard.