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
notka56 [123]
3 years ago
15

Jack is falling down the hill at a speed of 12 m/s. If Jack has a mass of 45 kg, what is his kinetic energy?

Physics
1 answer:
Troyanec [42]3 years ago
5 0

Answer:

K=3240J

Explanation:

speed=12m/s

m=45kg

K=½mv²

K=½(45•144)J=3240J

You might be interested in
Block A of mass M is on a horizontal surface of negligible friction. An identical block B is attached to block A by a light stri
miv72 [106K]

Answer:

T’= 4/3 T  

The new tension is 4/3 = 1.33 of the previous tension the answer e

Explanation:

For this problem let's use Newton's second law applied to each body

Body A

X axis

      T = m_A a

Axis y

     N- W_A = 0

Body B

Vertical axis

     W_B - T = m_B a

In the reference system we have selected the direction to the right as positive, therefore the downward movement is also positive. The acceleration of the two bodies must be the same so that the rope cannot tension

We write the equations

    T = m_A a

    W_B –T = M_B a

We solve this system of equations

     m_B g = (m_A + m_B) a

    a = m_B / (m_A + m_B) g

In this initial case

     m_A = M

     m_B = M

     a = M / (1 + 1) M g

     a = ½ g

Let's find the tension

    T = m_A a

    T = M ½ g

    T = ½ M g

Now we change the mass of the second block

    m_B = 2M

    a = 2M / (1 + 2) M g

    a = 2/3 g

We seek tension for this case

    T’= m_A a

    T’= M 2/3 g

   

Let's look for the relationship between the tensions of the two cases

   T’/ T = 2/3 M g / (½ M g)

   T’/ T = 4/3

   T’= 4/3 T

The new tension is 4/3 = 1.33 of the previous tension the answer  e

4 0
3 years ago
What is the relationship between a photons energy and its wavelength?
Elanso [62]

Answer:

The amount of energy is directly proportional to the photon's electromagnetic frequency and thus, equivalently, is inversely proportional to the wavelength. The higher the photon's frequency, the higher its energy. Equivalently, the longer the photon's wavelength, the lower its energy.

Explanation:

4 0
3 years ago
Which of the following is a personal decision that involves science?
malfutka [58]
A because its the only one that actually involves science
4 0
3 years ago
Сс<br> Explain the effect of Earth's gravity on objects on the<br> surface of Earth.
dem82 [27]

Answer:

The effect of gravity on object makes objects stable and not floating in the air . It also makes any object thrown up to return back

6 0
3 years ago
Which part of the ear sends a message to the brain that is recognized as sound
MrRissso [65]

Answer:

Inner Ear

Explanation:

Inner Ear or Cochlea

6 0
3 years ago
Other questions:
  • A nail in a pine board stops a 4.9-N hammer head from an initial downward velocity of 3.2 m/s in a distance of 0.45 cm. In addit
    11·1 answer
  • Scientists in a test lab are testing the hardness of a surface before constructing a building. Calculations indicate that the en
    8·1 answer
  • What is elasticity in polymer generally related to?
    12·2 answers
  • What is the equation for potential energy
    6·1 answer
  • A current of 3.2 Amps flows through a 7.0 Ω resistor in a circuit. Calculate the voltage.
    12·1 answer
  • The place kicker on a football team kicks a ball from ground level with an initial speed of 4.00 m/s at an angle of 29.0° above
    15·1 answer
  • A frictionless pendulum is made with a bob of mass 19.7 kg. The bob is held at height = 0.934 meter above the bottom of its traj
    12·1 answer
  • Suppose a square wave signal has a 65 percent duty cycle and an on-state voltage of 40 volts DC. What is the average DC voltage
    14·1 answer
  • Define 1 unit electricityl<br><br>​
    8·1 answer
  • After a massive-star supernova, what is left behind?.
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!