Which mechanism prevents uncontrolled energy escalation in a nuclear reactor?

💡 Explanation

Doppler broadening widens the neutron absorption spectrum of uranium because increased fuel temperature causes greater thermal motion. Increased neutron capture reduces reactivity; therefore thermal runaway is prevented, rather than driven by neutron moderation at lower energies.

• Which outcome occurs when molten steel cools imperfectly?
• Which outcome arises from substitutional impurity atoms modifying a silicon crystal lattice?
• Which outcome occurs when a high-power pulsed laser ablates steel?
• Which risk increases when a scanning tunneling microscope tip sharpness degrades?
• Which outcome is caused by increased electron tunneling in a flash memory cell array?
• Which outcome occurs when lubricating oil in a hydraulic system experiences increased shear rate?