Turn lights off, unplug electronics, and use solar energy
5m/s
100m
Explanation:
Average speed is sum of distance distance traveled in a given time by a body.
Average speed= 
Distance = 20m
time = 4s
Average speed =
= 5m/s
For the spaceship;
Distance covered = speed x time
Speed = 50m/s
time = 2s
Distance covered = 50 x 2 = 100m
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Average speed brainly.com/question/5063905
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The thermal energy was produced is 116J
<h3>What is the thermal energy produced?</h3>
Now we know that the frictional force produces the energy that is lost as heat as the body slides down the incline. The magnitude of the frictional force is obtained from;
Ff= μmgcosθ
Ff = 0.65 * 5.0 kg * 9.8 m/s^2 * cos 25
Ff = 29 N
Hence, the thermal energy is;
29 N * 4.0 m = 116J
Learn more about frictional force:brainly.com/question/1714663
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