Log In Start studying!

Select your language

Suggested languages for you:
Answers without the blur. Sign up and see all textbooks for free! Illustration

Q44PE

Expert-verified
College Physics (Urone)
Found in: Page 83

Answers without the blur.

Just sign up for free and you're in.

Illustration

Short Answer

A rescue helicopter is hovering over a person whose boat has sunk. One of the rescuers throws a life preserver straight down to the victime with an initial velocity of and observes that it takes to reach the water.

(a) List the known in this problem.

(b) How high above the water was the preserver released? Note that the downdraft of the helicopter reduces the effects of air resistance on the falling life preserver, so that an acceleration equal to that of gravity is reasonable.

b) 18.396 m

See the step by step solution

Step by Step Solution

Step 1: Given data

a)

The known value is as follows:

  • Initial velocity u= 1.40 ms .
  • Time is taken t= 1.8 s.
  • Acceleration ( in downward direction) =9.8 m/s2.
  • Final position = 0.

Step 2: Height of the life preserver

The height of the life preserver is equal to the distance.

For finding out the height, we have the equation

h=ut+12gt2

Here h is the height/distance, u is the initial velocity, g is the acceleration, and t is the time.

Substituting the values in the above expression, we get:

h=1.4×1.8+129.8×1.82=18.396 m

Hence the height of the lifesaver is around 18.396 m above the sea.

Most popular questions for Physics Textbooks

Icon

Want to see more solutions like these?

Sign up for free to discover our expert answers
Get Started - It’s free

Recommended explanations on Physics Textbooks

94% of StudySmarter users get better grades.

Sign up for free
94% of StudySmarter users get better grades.