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
inn [45]
3 years ago
5

Calculate the speed of a train that traveled 810 kilometers in 9 hours.

Physics
1 answer:
Naya [18.7K]3 years ago
8 0

Answer:

90 kilometers an hour

let me know if I'm wrong

You might be interested in
choose the correct anwer 9: the range of the gravitional force is given by A: 10_2m B:10_15m C: infinite D: 10_10m​
frosja888 [35]

Answer:

The answer is C

Explanation:

The magnitude of the gravitational force depends inversely on the square of the radial distance between the centers of the two masses. Thus, essentially, the force can only fall to zero, when the denominator that is r becomes infinite.

6 0
3 years ago
Which structure found in echinoderms can sometimes perform a similar function as a radula found in some mollusks? This Is A Scie
hammer [34]
I think it’s D which is the stomach if not I can get you someone that can help you
6 0
3 years ago
Read 2 more answers
A 150kg motorcycle starts from rest and accelerates at a constant rate along a distance of 350m. The applied force is 250N and t
notsponge [240]

A) The net force on the motorbike is 205.9 N

B) The acceleration of the motorbike is 1.37 m/s^2

C) The final speed is 5.2 m/s

D) The elapsed time is 3.80 s

Explanation:

A)

There are two forces acting on the motorbike:

- The applied force, F = 250 N, forward

- The frictional force, F_f, backward

The frictional force can be written as

F_f = \mu mg

where

\mu=0.03 is the coefficient of kinetic friction

m=150 kg is the mass of the motorbike

g=9.8 m/s^2 is the acceleration of gravity

Therefore the net force is given by

\sum F = F - F_f = F - \mu mg

And substituting, we find

\sum F=250 - (0.03)(150)(9.8)=205.9 N

2)

The acceleration of the motorbike can be found by using Newton's second law, which states that the net force is equal to the product between mass and acceleration:

\sum F = ma

where

m is the mass

a is the acceleration

In this problem, we have

\sum F = 205.9 N is the net force

m = 150 kg is the mass

Solving for a, we find the acceleration:

a=\frac{\sum F}{m}=\frac{205.9}{150}=1.37 m/s^2

C)

Since the motion of the motorbike is a uniformly accelerated motion, we can use the following suvat equation:

v^2-u^2=2as

where

v is the final velocity

u is the initial velocity

a is the acceleration

s is the distance covered

For this motorbike, we have:

u = 0 (it starts from rest)

a=1.37 m/s^2

s = 350 m

Solving for v,

v=\sqrt{u^2+2as}=\sqrt{0+2(1.37)(9.8)}=5.2 m/s

4)

For this part of the problem, we can use the following suvat equation:

v=u+at

where

v is the final velocity

u is the initial velocity

a is the acceleration

t is the elapsed time

Here we have:

v = 5.2 m/s

u = 0

a=1.37 m/s^2

Solving for t, we find

t=\frac{v-u}{a}=\frac{5.2-0}{1.37}=3.80 s

Learn more about Newton's laws of motion and accelerated motion:

brainly.com/question/11411375

brainly.com/question/1971321

brainly.com/question/2286502

brainly.com/question/2562700

brainly.com/question/9527152

brainly.com/question/11181826

brainly.com/question/2506873

brainly.com/question/2562700

#LearnwithBrainly

6 0
4 years ago
A 2 feet piece of wire is cut into two pieces and once a piece is bent into a square and the other is bent into an equilateral t
SpyIntel [72]

Answer:

Explanation:

Let x ft be used to make square and 2-x ft be used to make equilateral triangle.

each side of square = x/4

area of square = ( x /4 )²

Each side of triangle

= (2-x) /3

Area of triangle = 1/2 (2-x)²/9 sin 60

= √3 / 36 x (2-x)²

Total area

A = ( x /4 )² +√3 / 36 (2-x)²

For maximum area

dA/dx = 0

1/16( 2x ) -√3 / 36 x2(2-x) = 0

x / 8 - √3(2-x)/ 18 = 0

x / 8 - √3/9 + √3/18 x = 0

x ( 1/8 + √3/18 ) = √3/9

x(.125 +.096 ) = .192

x = .868 ft

3 0
3 years ago
In a wire with a 1.05 mm2 cross-sectional area, 7.93×1020 electrons flow past any point during 3.97 s. What is the current ????
34kurt

Answer:

The current in the wire is 31.96 A.

Explanation:

The current in the wire can be calculated as follows:

I = \frac{q}{t}

<u>Where</u>:

q: is the electric charge transferred through the surface

t: is the time      

The charge, q, is:

q = n*e

<u>Where</u>:

n: is the number of electrons = 7.93x10²⁰

e: is the electron's charge = 1.6x10⁻¹⁹ C

q = n*e = 7.93 \cdot 10^{20}*1.6 \cdot 10^{-19} C = 126.88 C

Hence, the current in the wire is:

I = \frac{126.88 C}{3.97 s} = 31.96 A

Therefore, the current in the wire is 31.96 A.

I hope it helps you!

3 0
3 years ago
Other questions:
  • a boy takes 15min to reach his school on bicycle.if the bicycle have speed of 2m/s the what is the distance between the house an
    15·1 answer
  • Calculate the wavelength of the electromagnetic radiation required to excite an electron from the ground state to the level with
    5·2 answers
  • If the distance between two objects increased, which of the following things could keep the force of gravity between the two obj
    7·1 answer
  • The acceleration of an object as a function of time is given by a(t) = (1.00 m/s2)t2. If displacement of the object between time
    7·1 answer
  • A bicycle tire has a pressure of 6.9 × 105 Pa at a temperature of 17.5°C and contains 2.00 L of gas. show answer Incorrect Answe
    6·1 answer
  • What geological forces drive tectonic movements?
    11·2 answers
  • A bowling ball traveling with constant speed hits the pins at the end of a bowling lane 16.5 m long. The bowler hears the sound
    14·1 answer
  • A stone is thrown horizontally with an initial speed of 10 m/s from the edge of a cliff. A stopwatch measures the stone's trajec
    11·1 answer
  • What is a four chord song??
    15·1 answer
  • The momentum of a falling rock is found to be 200 kg m/s. What is the mass of the rock if it falls with a velocity of 5.0 m/s
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!