Earth's Orbit and Circular Motion

The video tutorial explains how to calculate the length of an arc in a circle using the formula S = R x THETA, where the angle must be in radians. It demonstrates converting degrees to radians and simplifies the calculation for a circle with a radius of 3 cm and a central angle of 120 degrees. The tutorial then applies this concept to a real-world problem, calculating the distance the Earth travels in one month around the Sun, assuming a circular orbit with a radius of 93 million miles.

What is the radius of the circle in the initial problem?

• 2 centimeters

• 5 centimeters

• 3 centimeters

• 4 centimeters

What is the central angle given in the problem?

• 150 degrees

• 120 degrees

• 100 degrees

• 90 degrees

What is the formula for calculating arc length?

• S = R x THETA

• S = R + THETA

• S = R - THETA

• S = R / THETA

How do you convert degrees to radians?

• Multiply by pi/180

• Multiply by 180/pi

• Divide by pi

• Divide by 180

What is the arc length of the circle in centimeters?

• 6.28 cm

• 7.28 cm

• 5.28 cm

• 4.18 cm

What is the assumed shape of Earth's path around the Sun?

• Triangle

• Circle

• Square

• Ellipse

What is the radius of Earth's orbit in the application problem?

• 83 million miles

• 93 million miles

• 113 million miles

• 103 million miles

What fraction of a revolution does Earth complete in one month?

• 1/20

• 1/10

• 1/12

• 1/15

What is the value of theta used for Earth's orbit calculation?

• pi/6

• pi/5

• pi/4

• pi/7

Approximately how many million miles does Earth travel in one month?

• 68.7 million miles

• 58.7 million miles

• 48.7 million miles

• 38.7 million miles