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
Tom [10]
3 years ago
9

If you drop a rock off a cliff and it hits the ground 3 seconds later how tall is that cliff

Physics
1 answer:
skelet666 [1.2K]3 years ago
6 0

Answer:

Basic kinematics, negating drag and assuming ideal conditions, we use the equation:

d=vi*t+1/2*a*t^2

Since vi is 0 (we know this because you’re dropping it, not throwing it)…

…and the only acceleration acting on it is gravity, a=9.8 m/s^2…

…we get

d=1/2(9.8)(5)^2

Explanation:

Some quick mental math tells us that this is about 125 m.

Plugging it in, we find it to be 122.5 m.

You might be interested in
A firework is ignited, and explodes with a flash and a loud bang as it is blown apart. The system consists of: the firework, the
butalik [34]

The complete question is:

Study the scenario. A firework is ignited, and explodes with a flash and a loud bang as it is blown apart. The system consists of: the firework, the earth, and the air. which choice best describes how energy is transformed in the system?

A) When the firework is ignited, a chemical reaction absorbs energy from the surrounding environment. the energy is in several forms including sound and light, and mechanical energy of the fragments of the firecracker that are launched through the air. Eventually all the energy released is transformed into thermal energy.

B) When the firework is ignited, a chemical reaction releases energy in several forms, including sound, light, and the mechanical energy of the fragments being launched through the air. Eventually all the energy released is transformed into mechanical energy.

C) When the firework is ignited, a chemical reaction releases energy in several forms, including sound, light, and the mechanical energy of the fragments being launched through the air. Eventually all the energy released is transformed into thermal or mechanical energy.

D) When the firework is ignited, a chemical reaction absorbs energy from the surrounding environment. The energy is taken in in several forms including sound and light, and mechanical energy of the fragments being launched through the air. Eventually all the energy is transformed into thermal energy.

Answer:

C) When the firework is ignited, a chemical reaction releases energy in several forms, including sound, light, and the mechanical energy of the fragments being launched through the air. Eventually all the energy released is transformed into thermal or mechanical energy.

Explanation:

Energy is released from the system, not absorbed.

All the sound, light and movement of the debris is as a result of energy transformation from the chemical energy.

Eventually, most of the energy are finally wasted away as heat energy.

Some of the energy is used up by the flying particles from the fireworks.

8 0
3 years ago
Magnet A has twice the magnetic field strength of magnet B and pulls on magnet B with a force of 100 N. The amount of force that
son4ous [18]

The force exerted by the magnetic in terms of the magnetic field is,

F\propto B

Where B is the magnetic fied strength and F is the force.

Thus, if the magnetic A has twice magnetic field strength than the magnet B,

Then,

B_A=2B_B

Thus, the force exerted by the magnet B is,

\begin{gathered} F_B\propto B_B \\ F_B\propto\frac{B_A}{2} \\ F_B=\frac{F_A}{2} \\ F_B=\frac{100}{2} \\ F_B=50\text{ N} \end{gathered}

Thus, the force exerted by the magnet B on magnet A is 50 N.

The force exerted by the magnet A exerts on the magnet B is exactly 100 N as given.

Hence, the option B is the correct answer.

3 0
1 year ago
A certain car traveling at 97 km/h can stop in 47 m on a level road find the coefficient of friction
IrinaVladis [17]

The coefficient of friction between the road and the car's tire is determined as 0.78.

<h3>Acceleration of the car</h3>

The acceleration of the car is calculated as follows;

v² = u² - 2as

0 = u² - 2as

a = u²/2s

where;

  • u is the initial velocity = 97 km/h = 26.94 m/s

a = (26.94)²/(2 x 47)

a = 7.72 m/s²

<h3>Coefficient of friction</h3>

μ = a/g

μ = (7.72)/9.8

μ = 0.78

Learn more about coefficient of friction here: brainly.com/question/14121363

#SPJ1

5 0
2 years ago
An apple with a mass of 0.95 kilograms hangs from 3.0 meters above the ground. What is the potential energy of the apple
Vesnalui [34]

As Potential energy =mgh

m= 0.95kg

h=3 meter

g = 9.8 m/sec^2. ( acceleration due to gravity)

So P.E =(0.95)(9.8)(3)kgm^2/s^2

P.E =27.93 joules

3 0
3 years ago
If a transformer has a primary with 100 V and fifty coils, and a secondary that yields 20 V, how many coils are on the secondary
melomori [17]
Ideally, if all the magnetic of one winding cuts the other winding, and there isn't any loss in the transformer core or the resistance of the wire, then the voltage across each winding is proportional to the number of turns in its coil.

If you apply 100 V to a winding of 50 turns, then a winding that yields 20 volts
must be wound with

(20/100) of 50 turns = 10 turns
7 0
3 years ago
Other questions:
  • A mass on a spring will oscillate vertically when it is lifted and released how will the values of elastic potential energy and
    15·1 answer
  • Pure sodium metal placed in water will spark and ignite, as well as form bubbles and gas. What are the signs that this is a chem
    15·2 answers
  • Why is soap solution a better cleansing agent than ordinary water?
    9·1 answer
  • The successive ionization energies for an unknown element are listed below. To which family in the periodic table does the unkno
    5·2 answers
  • Consider a 10 gram sample of a liquid with specific heat 2 J/gK. By the addition of 400 J, the liquid increases its temperature
    6·1 answer
  • What is the is the 94th element of the periodic table
    12·1 answer
  • Instructions:Select the correct answer from the drop-down menu. The Longmenshan Fault is in China. This fault was created when t
    8·1 answer
  • A machine pulls a 46 kg trunk 3.0 m up a 42o ramp at constant velocity, with the machine's force on the trunk directed parallel
    5·2 answers
  • Sunlight above the Earth's atmosphere has an intensity of 1.36 kW/m2. If this is reflected straight back from a mirror that has
    5·1 answer
  • PLZ hurry! Thank you
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!