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
Mamont248 [21]
3 years ago
13

A stone released into the

Physics
1 answer:
mina [271]3 years ago
7 0

Answer:

h = 78.4  m

Explanation:

Given that,

A stone takes 4s for the stone to touch  the river's water surface.

We need to find the height of  the bridge from the water  level​.

Let the height be h. We can use the second equation of motion to find h. So,

h=ut+\dfrac{1}{2}gt^2\\\\ \because u=0\\\\So,\\\\h=\dfrac{1}{2}\times 9.8\times 4^2\\\\h=78.4\ m

So, the height of the bridge from the water level is 78.4  m.

You might be interested in
Almost everything in the universe orbits around a central object. The planets orbit the sun and moons orbit planets. The force M
Zolol [24]
The correct answer is "A". 'Gravity'. The Sun's gravity pulls on the planets to keep them in motion. Just like the Earth does to the moon.


I hope this helped you!

Brainliest answer is always appreciated!
8 0
3 years ago
Read 2 more answers
If a heat engine takes in 4565 kJ and gives up 2955 kJ during one cycle, what is the engine’s efficiency?
vodomira [7]

The engine efficiency is 64.73 %

<u>Explanation:</u>

Given data

To find the engine’s efficiency we have the formula,

Energy input- 4565 KJ

Energy output - 2955KJ

Efficiency= energy output/ energy input ×100%

 =2955/4565

  =0.6473 ×100

η               =64.73 %

The engine efficiency is 64.73 %

5 0
3 years ago
What is the name of the space telescope in low earth orbit that was launched in 1990?
Mrrafil [7]

The Hubble Space Telescope is a joint ESA/NASA project and was launched in 1990 by the Space Shuttle mission STS-31 into a low-Earth orbit 569 km above the ground. During its lifetime Hubble has become one of the most important science projects ever. Hope this helps! ~ Autumn :)

4 0
4 years ago
according to Newton's first law of motion what will an object in motion do when no external Force acts on it
Nataliya [291]
It will continue moving in a straight line at constant speed.
4 0
3 years ago
(25%) Problem 3: A bullet is fired horizontally into an initially stationary block of wood suspended by a string and remains emb
Rus_ich [418]

Answer:

Thus, the initial velocity of the bullet is 507.5 m/s.

Explanation:

mass of bullet, m = 0.0085 kg

mass of block, M = 0.99 kg

Height raised, h = 0.95 m

Let the initial velocity of bullet is u and the final velocity of block and bullet system is v.

Use conservation of energy

Potential energy of bullet bock system = kinetic energy of bullet block system

(M+m)\times g\times h = \frac{1}{2}\times \left ( M+m \right )v^{2}

v=\sqrt{2gh}

v=\sqrt{2\times 9.8\times 0.95}=4.32 m/s

Now use conservation of linear momentum

mu = (M+m) v

0.0085 x u = (0.99 + 0.0085) x 4.32

0.0085 u = 4.314

u = 507.5 m/s

Thus, the initial velocity of the bullet is 507.5 m/s.  

4 0
3 years ago
Other questions:
  • 5. In the process of electrolysis, current can flow through a liquid because
    11·1 answer
  • Three equal charges of magnitude 'e' are located at the vertices of an equilateral triangle of side 1m. Where should you place a
    8·1 answer
  • piston in a gasoline engine is in simple harmonic motion. The engine is running at the rate of 2 940 rev/min. Taking the extreme
    5·1 answer
  • by scale drawing, find the resultant of vectors 70N inclined at100N and direction of the resultant 100N​
    6·1 answer
  • Which property do metalloids share with nonmetals
    14·2 answers
  • A moving object is in equilibrium. What bests describes the motion of the object if mo force changes
    10·2 answers
  • Como se dice casa en náhuatl​
    15·1 answer
  • All waves change speed when they enter a new medium, but they don't always bend. When does bending occur?
    6·1 answer
  • Which statement best explains why a wet saw used to cut through a fine optical crystals is constantly lubricated with oil
    10·1 answer
  • Please help me do my homework
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!