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Lady bird [3.3K]
2 years ago
6

A lorry of mass 4000 kg is travelling at a speed of 4 m/s.

Physics
1 answer:
bulgar [2K]2 years ago
7 0

Answer:

KE = 32,000J

v = 8m/s

Explanation:

KE = .5*m*v²

KE = .5*4000kg*(4m/s)²

KE = 32,000J

32,000J = .5*1000kg*v²

v² = 64

v = 8m/s

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What is the maximum speed when the conditions are mass =450 kg, initial height= 30 m, and the roller coaster is initially at res
Zarrin [17]

Answer:

B. 24.2 m/s

Explanation:

Given;

mass of the roller coaster, m = 450 kg

height of the roller coaster, h = 30 m

The maximum potential energy of the roller coaster  due to its height is given by;

P.E_{max} = mgh\\\\PE_{max} = 450 *9.8*30\\\\PE_{max} = 132,300 \ J

P.E_{max} = K.E_{max} \ (law \ of \ conservation\ of \ energy)

K.E_{max} = \frac{1}{2}mv_{max}^2\\\\ v_{max}^2 = \frac{2K.E_{max}}{m}\\\\ v_{max}^2 = \frac{2*132300}{450}\\\\ v_{max}^2 =588\\\\v_{max} = \sqrt{588}\\\\  v_{max} = 24.2 \ m/s

Therefore, the maximum speed of the roller coaster is 24.2 m/s.

3 0
2 years ago
Can someone answer these questions
Aleks04 [339]

Answer:

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(via physicsclassroom.com)

3. The combustion throws out material with very high momentum and is, physically speaking, the action. In reaction to that that, the rocket moves away from it (upward when in starts and has the action underneath it)

4. To show the world that commercial manned space missions are safely possible. Some may also like the fact that the US can now do, or rather order, manned flights into space without the help of the russian space agency (Roskosmos).

5. Robert Behnken and Douglas Hurley

6. The international space station (ISS)

7. Yes, Stage 1 of the rocket landed on the drone ship. The crew opened the hatch to enter the space station after 21 hours and 39 minutes after the launch from Cape Canaveral.

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Also, due to Musks dream and efforts of SpaceX, space travel seems to get a lot cheaper.

That might indeed open the way back to the moon and further to the Mars for human space flight.

Governments such as the US planned on such things for decades, but changed plans ever since, and routinely changed leadership and the opinion on what's important.

Now Spaceflights can become less politically motivated and more commercially. That seems to be a more stable way over long periods of time.

(wrote most of it for you myself, even tough I'm not a native English speaker. would really appreciate the brainliest if you appreciate the work)

5 0
2 years ago
Read 2 more answers
A white dwarf star has a density of about 1.0 x 10^9 kg/m3. If the earth were to suddenly become as dense as a white dwarf star,
GalinKa [24]

Answer:

R = 98304.75 m = 98.3 km

Explanation:

The density of an object is given as the ratio between the mass of that object and the volume occupied by that object.

Density = Mass/Volume

Now, it is given that the density of Earth has become:

Density = 1 x 10⁹ kg/m³

Mass = Mass of Earth (Constant) = 5.97 x 10²⁴ kg

Volume = 4/3πR³ (Volume of Sphere)

R = Radius of Earth = ?

Therefore,

1 x 10⁹ kg/m³ = (5.97 x 10²⁴ kg)/[4/3πR³]

4/3πR³ = (5.97 x 10²⁴ kg)/(1 x 10⁹ kg/m³)

R³ = (3/4)(5.97 x 10¹⁵ m³)/π

R = ∛[0.95 x 10¹⁵ m³]

<u>R = 98304.75 m = 98.3 km</u>

6 0
2 years ago
What does the ozone layer protect us from?
djyliett [7]
For the future, Put the right subject please, The answer is to protect us from harmful UV rays, Which include UVA, UVB, And UBC.
6 0
2 years ago
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This speed is measured with respect to the space station the spacecraft was originally launched from. In interstellar space the
valentinak56 [21]

Answer:

15193.62 m/s

Explanation:

t = Time taken = 6.5 hours

u = Initial velocity = 0 (Assumed)

m = Mass of rocket = 1380 kg

F = Thrust force = 896 N

v = Final velocity

a = Acceleration of the rocket

Force

F=ma\\\Rightarrow a=\frac{F}{m}\\\Rightarrow a=\frac{896}{1380}\\\Rightarrow a=0.6493\ m/s^2

Equation of motion

v=u+at\\\Rightarrow v=0+0.6493\times 6.5\times 60\times 60\\\Rightarrow v=15193.62\ m/s

The velocity of the rocket after 6.5 hours of thrust is 15193.62 m/s

5 0
3 years ago
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