The earth's orbital radius is about 1.5 x 10 m. At this distance from the sun, the energy flux of sunlight is about 1.4kW/m². How much mass does the sun radiate as light in one second? ) A student pedaling a bicycle full throttle produces about one-half horsepower of useful power. (1 hp is equivalent to 746 W.) The human body is about 25 percent efficient: 75 percent of the food burned is converted to heat and 25 percent is converted to useful work. How long will the student have to ride to lose one pound by conversion of mass to energy? How come you do not have to exercise this long to lose a pound?
Stellar evolution
We may see thousands of stars in the dark sky. Our universe consists of billions of stars. Stars may appear tiny to us but they are huge balls of gasses. Sun is a star of average size. Some stars are even a thousand times larger than the sun. The stars do not exist forever they have a certain lifetime. The life span of the sun is about 10 billion years. The star undergoes various changes during its lifetime, this process is called stellar evolution. The structure of the sun-like star is shown below.
Red Shift
It is an astronomical phenomenon. In this phenomenon, increase in wavelength with corresponding decrease in photon energy and frequency of radiation of light. It is the displacement of spectrum of any kind of astronomical object to the longer wavelengths (red) side.
How do I use E = MC^2 to solve these questions?
![### Educational Content: Exercise and Energy
#### Problem Statement:
**(b)**
The Earth's orbital radius is about \(1.5 \times 10^{11} \, \text{m}\). At this distance from the sun, the energy flux of sunlight is about \(1.4 \, \text{kW/m}^2\). How much mass does the sun radiate as light in one second?
---
**(c)**
A student pedaling a bicycle full throttle produces about one-half horsepower of *useful* power. (1 hp is equivalent to 746 W.) The human body is about 25 percent efficient: 75 percent of the food burned is converted to heat and 25 percent is converted to useful work.
- How long will the student have to ride to lose one pound by conversion of mass to energy?
- How come you do not have to exercise this long to lose a pound?
#### Detailed Explanation:
**(b)**
For part (b), you need to determine the mass energy conversion for the Sun’s radiated energy.
1. **Calculate the total power output of the Sun:**
- The energy flux (\(1.4 \, \text{kW/m}^2\)) at the Earth's distance can be used with the surface area of a sphere (with radius being Earth's distance from the Sun) to find the total power.
- The surface area of the sphere: \[ A = 4 \pi R^2 \]
- \( R = 1.5 \times 10^{11} \, \text{m} \)
- Total power \( P = 1.4 \times 10^3 \, \text{W/m}^2 \times 4 \pi (1.5 \times 10^{11} \, \text{m})^2 \)
2. **Relate power to energy:**
- Energy radiated per second (\(E\)) is equal to the power output.
3. **Convert energy to mass using Einstein’s equation \(E = mc^2\):**
- Solve for the mass \(m\): \( m = \frac{E}{c^2} \)
- \( c \) is the speed of light \( (3 \times 10^8 \, \text{m/s}) \)
**(c)**
For part (c](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F2c1389c8-c38b-4f11-a551-6266360614a0%2F1ebd186b-1d6b-4c21-8f2b-2c6b3970703d%2Fnok7gx_processed.png&w=3840&q=75)

Trending now
This is a popular solution!
Step by step
Solved in 5 steps with 3 images









