Speed of the roller coaster at the top of the loop= 7.67 m/s
Explanation:
using the law of conservation of energy
KEi + PEi= KEf + PEf
KEi= kinetic energy at the top of the hill=0 because the car is at rest there.
PEi= potential energy at the top of the hill
PEf= potential energy at the top of the loop
KEf= kinetic energy at the top of the loop
Also kinetic energy= 1/ 2m v² and potential energy= mgh
m= mass
h= height
v= velocity
so 0+ mghi = 1/2mv² + mg h
500 (9.8)(10)+ 1/2 (500) v²= 500 ( 9.8) (7)
49000+250 v²= 34300
250v²= 14700
v²=58.8
v=7.67 m/s
The power dissipated by the LED is 20 Watts and the work done for 1 hour 15 minutes is 56.25 kJ.
<h3>What is electrical power?</h3>
Electrical power is the rate at which electrical work is done.
- Electrical power = voltage × current
The LED is 75% efficient means that 75% of power dissipated by the LED is converted to light.
Total power dissipated = 5 × 2.5 = 12.5 Watts
- Work done = power × time (in seconds)
Work done = 12.5 × (1 × 3600 + 15 × 60)
Work done = 56250 J = 56.25 kJ
Therefore, the power dissipated by the LED is 20 Watts and the work done for 1 hour 15 minutes is 56.25 kJ.
Learn more about electrical power and work done at: brainly.com/question/23901751
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Explanation:
When water vapor in the air comes into contact with something cool, like the ceiling of a tent, its molecules slow down and get closer together. When that happens, the gaseous water vapor turns back into liquid water droplets. That's condensation!