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
SSSSS [86.1K]
3 years ago
12

A swimmer bounces straight up from a diving board and falls feet first into a pool. She starts with a velocity of 4.00 m/s, and

her takeoff point is 1.80 m above the pool. (a) How long are her feet in the air? (b) What is her highest point above the board? (c) What is her velocity when her feet hit the water?
Physics
1 answer:
igor_vitrenko [27]3 years ago
6 0

Answer:

a) Her feet are in the air for 0.73+0.41 = 1.14 seconds

b) Her highest height above the board is 0.82 m

c) Her velocity when her feet hit the water is 7.16 m/s

Explanation:

t = Time taken

u = Initial velocity = 4 m/s

v = Final velocity

s = Displacement

a = Acceleration due to gravity = 9.81 m/s²

v=u+at\\\Rightarrow 0=4-9.81\times t\\\Rightarrow \frac{-4}{-9.81}=t\\\Rightarrow t=0.41\ s

s=ut+\frac{1}{2}at^2\\\Rightarrow s=4\times 0.41+\frac{1}{2}\times -9.81\times 0.41^2\\\Rightarrow s=0.82\ m

b) Her highest height above the board is 0.82 m

Total height she would fall is 0.82+1.8 = 2.62 m

s=ut+\frac{1}{2}at^2\\\Rightarrow 2.62=0t+\frac{1}{2}\times 9.81\times t^2\\\Rightarrow t=\sqrt{\frac{2.62\times 2}{9.81}}\\\Rightarrow t=0.73\ s

a) Her feet are in the air for 0.73+0.41 = 1.14 seconds

v=u+at\\\Rightarrow v=0+9.81\times 0.73\\\Rightarrow v=7.16\ m/s

c) Her velocity when her feet hit the water is 7.16 m/s

You might be interested in
A_______covalent bond is when atoms of two different elements form a covalent bond.
Jlenok [28]

Answer:

Explanation:    Covalent bonding occurs when pairs of electrons are shared by atoms. Atoms will covalently bond with other atoms in order to gain more stability, which is gained by forming a full electron shell. By sharing their outermost (valence) electrons, atoms can fill up their outer electron shell and gain stability.

4 0
2 years ago
A galvanometer is used as a
agasfer [191]

Answer:

detecting and indicating an electric current

4 0
3 years ago
La tensión en newtons necesaria para que una onda transversal cuya longitud de onda es 3.33 cm vibre a razón de 625 ciclos por s
NemiM [27]

Answer:

9.34 N

Explanation:

First of all, we can calculate the speed of the wave in the string. This is given by the wave equation:

v=f \lambda

where

f is the frequency of the wave

\lambda is the wavelength

For the waves in this string we have:

f=625 Hz, since it completes 625 cycles per second

\lambda=3.33 cm = 0.033 m is the wavelength

So the speed of the wave is

v=(625)(0.0333)=20.6 m/s

The speed of the waves in a string is related to the tension in the string by

v=\sqrt{\frac{T}{\mu}} (1)

where

T is the tension in the string

\mu=\frac{m}{L} is the linear density

In this problem:

m=16.5 g = 16.5\cdot 10^{-3} kg is the mass of the string

L = 0.75 m is the its length

Solving the equation (1) for T, we find the tension:

T=\mu v^2 = \frac{m}{L} v^2 = \frac{16.5\cdot 10^{-3}}{0.75}(20.6)^2=9.34 N

8 0
3 years ago
Why does the area around the equator stay about the same temperature year round?
Verdich [7]
Axial Tilt and Sun Energy

This axial tilt means that during the Earth's journey around the sun the poles receive varying amounts of sunlight. The equator, however, receives relatively consistent sunlight all year. The consistency of energy means the equator's temperature stays relatively constant all year.
3 0
3 years ago
How much would it cost to cover the entire land area of the U.S. in dollar bills?
agasfer [191]

Answer:

  $900 trillion

Explanation:

If Alaska is 20% of the contiguous US, then the approximate area of interest is ...

  1200 miles × 3000 miles = 3.6×10^6 square miles.

The size of a dollar bill is about ...

  (6.5 cm)·(15.5 cm) = 100.75 cm^2

One mile is 160,934.4 cm, so 1 square mile is about ...

  1 mi^2 = (160,934.4 cm)^2 ≈ 2.59·10^10 cm^2

The number of dollars of interest is then ...

  (3.6 · 10^6 mi^2)(2.59 · 10^10 cm^2)/(100.75 cm^2) ≈ 9.3·10^14

  ≈ 930 × 10^12 . . . dollars

It would cost about 900 trillion dollars to cover the land area of the US in $1 bills.

7 0
3 years ago
Other questions:
  • A solenoid with 3,000.0 turns is 70.0 cm long. If its self-inductance is 25.0 mH, what is its radius? (The value of μ0 is 4π x 1
    5·1 answer
  • (Atwood’s Machine): Two masses, 9 kg and 12 kg, are attached by a lightweight cord and suspended over a frictionless pulley. Whe
    15·2 answers
  • This is a sign of a chemical reaction that involves a new color being created during the reaction.
    6·1 answer
  • A dolphin emits a sound wave that hits a target 120 m away. The wave reflects back from the target to the dolphin. If the Bulk m
    9·1 answer
  • A circuit has a source voltage of 50v and a current of 10a. what is the power in watts
    11·1 answer
  • Suppose an individual is lying on his stomach with sheets of paper stacked on his back. If each sheet of paper has a mass of 0.0
    12·1 answer
  • What is the difference between celestial and terrestrial in planetary terms? Someone please answer
    15·1 answer
  • If the power developed in an electric circuit is doubled the energy used in one second is
    14·1 answer
  • If you use a hair dryer, what type of electrical transformation is this?
    5·1 answer
  • If Bill threw a ball straight up on the Moon (g=1.6 m/s2) with a starting velocity of 22m/s from a cliff and it fell past him an
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!