1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
GalinKa [24]
2 years ago
11

A life preserver is thrown from an helicopter straight down to a person in distress. The initial velocity of the life preserver

is 1.60 m/s and it takes 2.3 s to reach the water. (a) List the knowns in this problem. (b) How high above the water was the preserver released? Note Ignore air resistance.
Physics
1 answer:
Leno4ka [110]2 years ago
6 0

Answer:29.627 m

Explanation:

Given

Initial velocity of life preserver(u) is 1.6 m/s

it takes 2.3 s to reach the water

using equation of motion

v=u+at

v=1.6+9.81\times 2.3

v=24.163 m/s

Let s be the height of life preserver

v^2-u^2=2gs

24.163^2-1.6^2=2\times 9.81\times s

s=\frac{581.29}{2\times 9.81}

s=29.627 m

You might be interested in
An electron, moving south, enters a uniform magnetic field. Because of this uniform magnetic field, the electron curves upward.
Flura [38]

Answer:

Towards the west

Explanation:

Magnetic force is the interaction between a moving charged particle and a magnetic field.

Magnetic force is given as

F = q (V × B)

Where F is the magnetic force

q is the charge

V is the velocity

B is the magnetic field

V×B means the cross product of the velocity and the magnetic field

NOTE:

i×i=j×j×k×k=0

i×j=k.  j×i=-k

j×k=i.  k×j=-i

k×i=j.  i×k=-j

So, if the electron is moving southward, then, it implies that the velocity of it motion is southward, so the electron is in the positive z-direction

Also, the electron is curved upward due to the magnetic field, this implies that the force field is directed up in the positive y direction.

Then,

V = V•k

F = F•j

Then, apply the theorem

F •j = q ( V•k × B•x)

Let x be the unknown

From vector k×i =j.

This shows that x = i

Then, the magnetic field point in the direction of positive x axis, which is towards the west

You can as well use the Fleming right hand rule

The thumb represent force

The index finger represent velocity

The middle finger represent field

3 0
2 years ago
A train travels a distance of 2000 km at an average speed of 120 km per hour. How long did the trip take? SHOW WORK
Igoryamba
S = d/t, s = 120, d = 2000, t = ?
Input the values,
120 = 2000/t
Make t the subject of the formula by cross multiplying, Therefore,
120t = 2000
Divide both sides by 120
t = 16.7hrs  to 1 decimal place.
If you're asked to convert it, you can.


6 0
3 years ago
How does the ratio of tin to copper affect the properties of the alloy bronze?
Pani-rosa [81]

Answer:

Stronger and harder than either of the pure metals

Explanation:

7 0
1 year ago
Given one mole of diamond vs one mole of graphite,
grandymaker [24]

Answer:

The pressure is P= -  6.39*10^8Pa

The temperature is T =1218.63 K

Explanation:

Generally Gibbs free energy is mathematically represented as

                   G = E + PV -TS

   Where  E is the enthalpy

               PV is the pressure volume energy (i.e PV energy)

                S  is the entropy

                T is the temperature

For stability to occur the Gibbs free energy must be equal to zero

Considering Diamond

  So at temperature of  T = 300 K

         E + PV - TS = 0

making P the subject

          P = \frac{TS-E}{V}

Now substituting 300 K for T , 2900 J  for E ,

                              3.42cm^3 = \frac{3.42}{1*10^6} = 3.42*10^{-6}m^3 for V and 2.38 J/K for S

     P = \frac{(300 * 2.38)- 2900}{3.42*10^{-6}}

         P= -  6.39*10^8Pa

The negative sign signifies the direction of the pressure

Given that  P = 1*0^5Pa

making T the subject

            T = \frac{PV+E}{S}

Substituting into the equation

            T = \frac{1*10^5 * 3.42 *10^{-6}+2900}{2.38}

                T =1218.63 K

             

         

7 0
3 years ago
Read 2 more answers
If the out come of a 1.0-kg ball moving at 3.0 m/s is 4.5 kinetic energy what would the kinetic energy be if the mass and speed
Flauer [41]

Answer: KE = 36 J

Explanation: Solution:

KE = 1/2 mv²

= 1/2 ( 2 kg)(6 m/s)²

= 36 J

7 0
2 years ago
Other questions:
  • Someone got this paper?
    14·1 answer
  • A single point charge q is located at the center of both an imaginary cube and an imaginary sphere. How does the electric flux t
    7·1 answer
  • A 75.0-kg man steps off a platform 3.10 m above the ground. he keeps his legs straight as he falls, but his knees begin to bend
    14·1 answer
  • Suppose a wheel with a tire mounted on it is rotating at the constant rate of 2.59 times a second. A tack is stuck in the tire a
    11·1 answer
  • An object 7 cm tall is placed at different locations in front of a concave mirror whose radius of curvature is 64 cm. Determine
    15·1 answer
  • A student in Denver (altitude = 1 mile = 1609 m above sea level) brings a physics book of mass 1.3 kg to the top of a ten story
    6·1 answer
  • Newton’s second law of motion addresses the relationship between what two variables that influence the force on a body?
    10·2 answers
  • 5. (10 points) Which of the following statements is(are) correct: A. Resistivity purely depends on internal properties of the co
    5·1 answer
  • Good evening! Can someone please answer this, ill give you brainliest and your earning 50 points. Would be very appreciated.
    11·2 answers
  • Modern observations have shown that the geometry of the universe is ____.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!