Author Question: If the y component of the initial velocity for a projectile is 10m/s, how long will the projectile stay in the? (Read 1711 times)

Millan

  • Sr. Member
  • ****
  • Posts: 368
Need help on homework; I can't find the answer anywhere. Please help!

If the y component of the initial velocity for a projectile is 10m/s, how long will the projectile stay in the air before coming back to the original level?

A.) 10s
B.) 20s
C.) 2s
D.) 1s

Thank you!



TI

  • Sr. Member
  • ****
  • Posts: 434
Answer C

When the projectile reaches the maximal height Vy = 0

Vy = V°y - gt  if Vy = 0 ---- V°y = g t and t = V°y /g = 10 / 9.8 = 1.02041 s

Y = V°y t - 1/2 g t^2 --- 10 * 1.02041 - 0.5 * 9.8 * 1.04123= 10.2041 - 5.10204 = 5.1020 m

The duration of the free fall is identical in the time of rise = 1.02041

Time total = 1.02041 * 2 = 2.0408 s

Goodbye
« Last Edit: Jun 23, 2013 by Celeste »



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.

Did you know?

The largest baby ever born weighed more than 23 pounds but died just 11 hours after his birth in 1879. The largest surviving baby was born in October 2009 in Sumatra, Indonesia, and weighed an astounding 19.2 pounds at birth.

Did you know?

The average office desk has 400 times more bacteria on it than a toilet.

Did you know?

Despite claims by manufacturers, the supplement known as Ginkgo biloba was shown in a study of more than 3,000 participants to be ineffective in reducing development of dementia and Alzheimer’s disease in older people.

Did you know?

The cure for trichomoniasis is easy as long as the patient does not drink alcoholic beverages for 24 hours. Just a single dose of medication is needed to rid the body of the disease. However, without proper precautions, an individual may contract the disease repeatedly. In fact, most people develop trichomoniasis again within three months of their last treatment.

For a complete list of videos, visit our video library