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
Vika [28.1K]
3 years ago
8

A 12.0 kg rock slides off the edge of a bridge and falls into the water 25.0 meters below. what is the kinetic energy of the roc

k just as it hits the water?
Physics
1 answer:
Pavel [41]3 years ago
7 0
During the fall, all the initial potential energy of the rock 
U=mgh
has converted into kinetic energy of motion
K= \frac{1}{2}mv^2
where h is the initial height of the rock, m its mass, and v its velocity just before hitting the water. So, for energy conservation, we have
U=K
and so we can find the value of K, the kinetic energy of the rock just before hitting the ground:
K=U=mgh = (12.0 kg)(9.81 m/s^2)(25.0 m)=2943 J
You might be interested in
A newly discovered particle, the SPARTYON, has a mass 945 times that of an electron. If a SPARTYON at rest absorbs an anti-SPART
Gennadij [26K]

Answer:

\nu =1166\times 10^{20}Hz  

Explanation:

We have given the rest mass of SPARTYON = 945 times of mass of electron

We know that mass of electron =9.11\times 10^{-31}kg

So mass of SPARTYON =945\times 9.11\times 10^{-31}=8608.95\times 10^{-31}kg

Speed of light c=3\times 10^8m/sec

According to Einstein equation energy is given by

E=mc^2=8608.95\times 10^{-31}\times (3\times 10^{8})^2=77480.55\times 10^{-15}j

Now according to planks's rule

Energy is given by

E=h\nu , here h is plank's constant h=6.6\times 10^{-34}

So 77480.55\times 10^{-15}=6.6\times 10^{-34}\nu

\nu =1166\times 10^{20}Hz  

3 0
3 years ago
A 5 kg object near Earth's surface is released from rest such that it falls a distance of 10 m. After the object falls 10 m, it
makkiz [27]

Answer:D

Explanation:

Given

mass of object m=5 kg

Distance traveled h=10 m

velocity acquired v=12 m/s

conserving Energy at the moment when object start falling and when it gains 12 m/s velocity

Initial Energy=mgh=5\times 9.8\times 10=490 J

Final Energy=\frac{1}{2}mv^2+W_{f}

=\frac{1}{2}\cdot 5\cdot 12^2+W_{f}

where W_{f} is friction work if any

490=360+W_{f}

W_{f}=130 J

Since Friction is Present therefore it is a case of Open system and net external Force is zero

An open system is a system where exchange of energy and mass is allowed and Friction is acting on the object shows that system is Open .

4 0
3 years ago
A speeding car collides with an unlucky bug flying across the road. Which explains why the impact doesn’t equally damage the car
velikii [3]
The bug was a lot smaller than the car, that's for sure. The car is bigger and sturdier, while the bug is smaller and frail. The bug is so frail, that rather that putting a dent in the car, it splatters all over the car. The bug is very damaged (obviously), while the car just needs a good wash.
8 0
3 years ago
What kind of tectonic plate boundary must have existed in the past where copper deposits are found, based on the way they are fo
Maksim231197 [3]

Answer:

older plates that are subducting almost perpendicularly, and when the location is far away from the edge of other tectonic plates, are the most likely areas for copper deposits to form

Explanation:

5 0
3 years ago
A car travels a distance of 540km in 6hours.What speed did he travel at?​
Sloan [31]

Answer: 90 km/hr

Explanation:

Speed= distance divided by time

540/6

= 90km/hr

5 0
3 years ago
Other questions:
  • Why is our (a person's) gravitational pull NOT as strong as the Earth's gravitational pull
    13·1 answer
  • At a pressure 43 kPa, the gas in a cylinder has a volume of 12 liters. Assuming temperature remains the same, if the volume of t
    13·1 answer
  • An 8 Ω resistor is connected to a battery. The current that flows in the circuit is 2 A. Calculate the voltage of the battery.
    6·1 answer
  • You are on a train that is traveling at 3.0 m/s along a level straight track. Very near and parallel to the track is a wall that
    8·1 answer
  • As a gas or liquid increases in heat, what direction will it naturally move?
    9·1 answer
  • Some populations have cooperative relationships. This is where:
    10·1 answer
  • An LED is useful because when a current passes through it, it gives out... what?
    7·1 answer
  • Explain how wind erosion changes land forms
    5·1 answer
  • PLS HELP!!! WILL GIVE BRAINLIEST
    15·2 answers
  • A magnet gets demagnetized when it is heated.​
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!