During its final days as a red giant, the Sun will reach a peak luminosity of about 3000LSun. Earth will therefore absorb about 3,000 times as much solar energy as it does now, and it will need to radiate 3,000 times as much thermal energy to keep its surface temperature in balance. Part A Estimate the temperature Earth's surface will need to attain in order to radiate that much thermal energy. You will need to use the formula for emitted power per unit area. (Assume that Earth's temperature today is around 300 K.)

Date chapter motion and speed review part a. vocabulary review directions: write the terms that match each description below in thes complete the sentence in number 13. ich each description below in the spaces provided. the boxed letters will 1. equal forces acting in opposite directions (2 words) 2. occurs when an object's velocity decreases (2 words) 3. sum of all forces acting on an object (2 words) 4. total distance divided by total time (2 words) 5. name for the slant of a line on a graph 6. distance divided by time 7. a push or a pull exerted on a body or object 8. distance and direction of an object from its starting point 9. tendency to resist change in motion 10. measure of how far an object has moved 11. speed and direction of motion 12. rate of change of position at a specific point in time (2 words) 13. the rate of change in velocity is called motion and spe

For problems 1-3, consider a simple dc brush motor with a permanent magnet stator. with an an consider a simple dc brush motor with a permanent magnet ae supply voltage of 100 v, the no-load speed of the motor is 1000 rpm. this motor can provide a torque of 1.9 n-m at 800 rpm drawing a current of 2 a current are both zero at no load.) 1. with an armature supply voltage of 100 v, the motor is operated at 900 rpm. what is the motor torque? what is the mechanical power delivered by the motor? what is the current draw? what is the electrical power input? what is the energy efficiency of the motor? with an armature supply voltage of 100 v, the motor is operated at 1100 rpm (where it acts as a generator). what torque input is required? what mechanical power is required what current is generated? what is the electrical power generated? what is the energy efficiency of the motor acting as a generator? 2. with an armature supply voltage raised to 120 v, the motor is operated at 1000 rpm. what is the no-load speed? what is the motor torque? what is the mechanical power delivered by the motor? what is the current draw? what is the electrical power input what is the energy efficiency of the motor? 3.

In science and physics what is the standard unit of measure for speed?