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
Vilka [71]
2 years ago
11

A fast-moving car has 0.5 MJ of kinetic energy.

Physics
1 answer:
DerKrebs [107]2 years ago
6 0

Answer:

-0.5 MW

Explanation:

For this we can use the principle of work and energy, which states that:

T₁ + ∑U₁₋₂ = T₂

Where T is kinetic energy (in situations one and two) and U is the sum of all work done (between situations one and two).

So, since the car is first moving with a kinetic energy of 0.5 MJ:

T₁ = 0.5 MJ = 0.5 · 10⁶ J

On top of this, we know that the car comes to a halt, using this as situation 2:

T₂ = 0 J

Filling in the equation:

⇒ 0.5 · 10⁶ + U = 0

⇒ U = -0.5· 10⁶ [W] (unit of work is watts)

       = -0.5 MW

Thinking about the sign convention, we see that the brake force will point to the back of the car (backward), and the distance the car will travel before stopping will be forward, oposite directions and thus negative work.

You might be interested in
I need help now please help me
alexandr1967 [171]
The correct answer is C. Plug in x and y value for answers to see if they work. For example, 9/3 = 3. So C is the answer.
8 0
3 years ago
You are working as an assistant to an air-traffic controller at the local airport, from which small airplanes take off and land.
Alika [10]

Answer:

d = 2021.6 km

Explanation:

We can solve this distance exercise with vectors, the easiest method s to find the components of the position of each plane and then use the Pythagorean theorem to find distance between them

Airplane 1

Height   y₁ = 800m

Angle θ = 25°

           cos 25 = x / r

           sin 25 = z / r

           x₁ = r cos 20

           z₁ = r sin 25

          x₁ = 18 103 cos 25 = 16,314 103 m = 16314 m

          z₁ = 18 103 sin 25 = 7,607 103 m= 7607 m

2 plane

Height   y₂ = 1100 m

Angle θ = 20°

          x₂ = 20 103 cos 25 = 18.126 103 m = 18126 m

          z₂ = 20 103 without 25 = 8.452 103 m = 8452 m

The distance between the planes using the Pythagorean Theorem is

         d² = (x₂-x₁)² + (y₂-y₁)² + (z₂-z₁)²2

Let's calculate

        d² = (18126-16314)²  + (1100-800)² + (8452-7607)²

        d² = 3,283 106 +9 104 + 7,140 105

        d² = (328.3 + 9 + 71.40) 10⁴

        d = √(408.7 10⁴)

        d = 20,216 10² m

        d = 2021.6 km

7 0
3 years ago
A 1.0-kg block moving to the right at speed 3.0 m/s collides with an identical block also moving to the right at a speed 1.0 m/s
____ [38]

Answer:

Speed of both blocks after collision is 2 m/s

Explanation:

It is given that,

Mass of both blocks, m₁ = m₂ = 1 kg

Velocity of first block, u₁ = 3 m/s

Velocity of other block, u₂ = 1 m/s

Since, both blocks stick after collision. So, it is a case of inelastic collision. The momentum remains conserved while the kinetic energy energy gets reduced after the collision. Let v is the common velocity of both blocks. Using the conservation of momentum as :

m_1u_1+m_2u_2=(m_1+m_2)v

v=\dfrac{m_1u_1+m_2u_2}{(m_1+m_2)}

v=\dfrac{1\ kg\times 3\ m/s+1\ kg\times 1\ m/s}{2\ kg}

v = 2 m/s

Hence, their speed after collision is 2 m/s.

7 0
3 years ago
The combined-gas law relates which of these?
Fofino [41]
The combined-gas law relates which temperature, pressure and volume.

Temperature=T
Pressure=P
Volume=V

(P₁*V₁) / T₁=(P₂*V₂) / T₂

D. Temperature, pressuere and volume.
5 0
3 years ago
1. The resistance of an electric device is 40,000 microhms. Convert that measurement to ohms.
lidiya [134]

Answer:

The answer would be 0.04ohms.

Explanation:

Hopefully this helps

4 0
2 years ago
Read 2 more answers
Other questions:
  • Mechanical advantage of a simple machine is 4,what does it mean?​
    13·1 answer
  • Which of the following occurs as light travels farther from its source?
    11·1 answer
  • Why do X-Ray technicians stand behind a shield when giving X-Rays to patients?
    11·2 answers
  • The unit of length most suitable for measuring the thickness of a cell phone is a
    13·1 answer
  • A rock falls from a tower that is 320 feet high. As it is​ falling, its height is given by the formula h equals 320 minus 16 t s
    15·1 answer
  • Which statement is true with respect to an atom?
    5·2 answers
  • A longitudinal wave is observed. Exactly 6 crests are observed
    15·1 answer
  • A heavier person will have a lower blood level due to a greater amount of ___ in their
    12·1 answer
  • Which of these is not a standard unit?<br> a. second <br> b. metre<br> c. hand span <br> d. gram
    15·2 answers
  • light that is polarized along the vertical direction is incident on a sheet of polarizing material. only 87% of the intensity of
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!