« previous next »

Author Question: The Drake equation allows us to estimate the number of A) intelligent civilizations that have ... (Read 50 times)

sdfghj

  • Hero Member
  • *****
  • Posts: 552
on: Jul 27, 2018
The Drake equation allows us to estimate the number of
 
  A) intelligent civilizations that have existed in our galaxy during its entire lifetime
  B) habitable planets on which life has arisen
  C) intelligent civilizations capable of traveling to the Earth
  D) intelligent civilizations capable of communicating in our galaxy now

Question 2

A mine railroad car, of mass 200 kg, rolls with negligible friction on a horizontal track with a speed of 10.0 m/s. A 70. kg stunt man drops straight down a distance of 4.0 m, and lands in the car.
 
  How fast will the car be moving after this happens?


nixon_s

  • Sr. Member
  • ****
  • Posts: 359
Reply #1 on: Jul 27, 2018
Answer to Question 1

D

Answer to Question 2

7.41 m/s


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

Stevens-Johnson syndrome and Toxic Epidermal Necrolysis syndrome are life-threatening reactions that can result in death. Complications include permanent blindness, dry-eye syndrome, lung damage, photophobia, asthma, chronic obstructive pulmonary disease, permanent loss of nail beds, scarring of mucous membranes, arthritis, and chronic fatigue syndrome. Many patients' pores scar shut, causing them to retain heat.

Did you know?

Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.

Did you know?

The human body's pharmacokinetics are quite varied. Our hair holds onto drugs longer than our urine, blood, or saliva. For example, alcohol can be detected in the hair for up to 90 days after it was consumed. The same is true for marijuana, cocaine, ecstasy, heroin, methamphetamine, and nicotine.

Did you know?

Street names for barbiturates include reds, red devils, yellow jackets, blue heavens, Christmas trees, and rainbows. They are commonly referred to as downers.

Did you know?

The Centers for Disease Control and Prevention (CDC) was originally known as the Communicable Disease Center, which was formed to fight malaria. It was originally headquartered in Atlanta, Georgia, since the Southern states faced the worst threat from malaria.

Part A - Calculating the expected number of each phenotype Part A - Calculating the expected number of each phenotype
Father’s Age and the Number of de novo Mutations Father’s Age and the Number of de novo Mutations
Number and label designations for oxygen sensors. Bank 1 is the bank where cylinder number 1 is ... Number and label designations for oxygen sensors. Bank 1 is the bank where cylinder number 1 is ...
Determine the # of real roots from the equation Determine the # of real roots from the equation
The position of an object that is oscillating on a spring is given by the equation x = (18.3 ... The position of an object that is oscillating on a spring is given by the equation x = (18.3 ...
Use the Henderson-Hasselbalch equation to perform the following calculations. Use the Henderson-Hasselbalch equation to perform the following calculations.
Video: Endocytosis - pinocytosis, receptor mediated and Transcytosis

For a complete list of videos, visit our video library