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
Elenna [48]
3 years ago
12

Four identical balls are thrown from the top of a cliff, each with the same speed. The

Physics
1 answer:
Jlenok [28]3 years ago
6 0

Answer:

the speed and the kinetic energy of the first and fourth ball are equal, while the speed and kinetic energy of the second and third balls are equal

Explanation:

The kinetic energy, K.E. = (1/2) × m × v²

The velocity of the ball, v = u × sin(θ)

Where;

u = The initial velocity of the ball

θ = The reference angle

1) For the ball thrown straight up, we have;

θ = 90°

∴ v = u

The final velocity of the ball as it strikes the ground is v₂ = u² + 2gh

Where;

h = The height of the cliff

∴ K.E. = (1/2) × m × (u² + 2gh)²

2) For the second ball thrown 30° to the horizontal, we have;

K.E. = (1/2) × m × ((u×sin30)² + 2·g·h)² = K.E. = (1/2) × m × ((0.5·u)² + 2·g·h)²

3) For the third ball thrown at 30° below the horizontal, we have;

K.E. = (1/2) × m × ((u×sin30)² + 2·g·h)² = K.E. = (1/2) × m × ((0.5·u)² + 2·g·h)²

4)  For the fourth ball thrown straight down, we have;

K.E. = (1/2) × m × (u² + 2gh)²

Therefore, as the ball strike the ground, the speed and the kinetic energy of the first and fourth ball are equal, while the speed and kinetic energy of the second and third balls are equal

Learn more about object kinetic energy of object if free fall here;

brainly.com/question/14872097

You might be interested in
A spring has a natural length of 28.0 cm. If a 23.0-N force is required to keep it stretched to a length of 36.0 cm, how much wo
krek1111 [17]

Answer:

0.23 J

Explanation:

k*(36 - 28) = 23

so k = 23/8 N/cm

W = k(32 - 28)²/2 = 23/8 * 4²/2 = 23 N-cm = 0.23 J

4 0
2 years ago
A truck accelerating at 0.0083 meters/second2 covers a distance of 5.8 × 104 meters. If the truck's mass is 7,000 kilograms, wha
zhannawk [14.2K]
Work done = force * distance moved (in direction of the force)

force= mass* acceleration 

force=58.1N

58.1*(5.8*10^4)
=3,369,800 J
7 0
3 years ago
Read 2 more answers
Define s.i unit of force explanation
kvv77 [185]
<h3><u>Answer</u> :</h3>

◈ As per newton's second law of motion, Force is defined as the product of mass and acceleration.

Mathematically,

\dag\:\boxed{\bf{\purple{F=ma}}}

Unit of mass : kg

Unit of acceleration : m/s²

Therefore,

Unit of force ➠ <u>kg m/s²</u>

SI unit : <u>N (newton)</u> or <u>kg m/s²</u>

3 0
3 years ago
Describe the orbit in which planets revole around the sun
Novay_Z [31]
Planets orbit the sun in the paths which are known as elliptical orbit. Each planet has its own orbit around the sun and direction in which all the planets orbit around the sun are the same. These orbits were well explained by the astronomer Kepler. The gravity of the Sun keeps the planets in their orbits. They stay in their orbits because there is no other force in the Solar System which can stop them.
7 0
2 years ago
A motor-driven winch pulls a 50.0 kg student 5.00 m up the rope at a constant speed of 1.25 m/s. how much power does the motor u
nadya68 [22]
Power is the rate work done given by dividing work done by unit time. It is measured in watts equivalent to J/s.
In this case the force by the student is mg = 490 N (taking g as 9.8m/s²)
Work done is given by force × distance,
Therefore, Power =(force × distance)/ time, but velocity/speed =distance/time
Thus, Power = force × speed/velocity
                     = 490 N × 1.25
                     = 612.5 J/S (Watts)
Hence, power will be 612.5 Watts.
7 0
3 years ago
Other questions:
  • The presence of a uniform magnetic field may be detected by using a
    6·2 answers
  • Explain what makes some materials better than others in how they insulate.
    6·1 answer
  • When the power in their house unexpectedly went off, Radhika's mother said that she would check and replace the fuse. What exact
    13·1 answer
  • n hydrogen, the transition from level 1 to level 2 has a rest wavelength of 121.6 nm. Suppose you see this line at a wavelength
    7·1 answer
  • (a) How much gravitational potential energy (relative to the ground on which it is built) is stored in the Great Pyramid of Cheo
    12·1 answer
  • Can someone help me please
    10·1 answer
  • Which statement best describes the change in an objects momentum if the net force acting on the object is greatly increased ?
    9·2 answers
  • While waiting for his Mom to come out of the hairdresser's, Sean accidentally puts the car in gear and it begins to roll forward
    6·1 answer
  • Un vehiculo se desplaza con movimiento rectilio uniforme. Sabiendo que recorre 90 km en 3 horas. Averiguo la velocidad en m/s.
    11·1 answer
  • A 10kg box accelerates forward at a rate of 12 m/s^2. What is the force acting on the box?
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!