A train traveled 280km in 3.5 hours. what was the average speed in m/s?

Please help please help

Inessa [10]

Answer: p= m/v so 90kg/.075m^3 = 1,200

2a. .35 m 1.1 m and .015 m

2b. 35 cm x 110 cm x 1.5 cm = 5,775 cm^3 = 57.75 m^3

mass= pv

2700•57.75= 155,925 kg

mass= 155,925 kg

volume= 57.75 m^3

Explanation: physics

6 0

3 years ago

Death Star has a diameter of 160,000m and a mass of 5.1e17kg. Millennium Falcon has a mass of 1.36e6kg (data from Wookieepedia)

lions [1.4K]

Answer:

7229 N

Explanation:

The gravitational force between the Death Star and the Millenium Falcon is given by:

$F=G\frac{mM}{R^2}$

where

$G=6.67\cdot 10^{-11} m^3 kg^{-1} s^{-2}$ is the gravitational constant

$M=5.1\cdot 10^{17} kg$ is the mass of the Death Star

$m=1.36\cdot 10^6 kg$ is the mass of the Millennium Falcon

$R=\frac{160,000 m}{2}=80,000 m$ is the radius of the Death Star

Substituting numbers into the equation, we find the force

$F=(6.67\cdot 10^{-11})\frac{(1.36\cdot 10^6 kg)(5.1\cdot 10^{17} kg)}{(80,000 m)^2}=7229 N$

5 0

3 years ago

A test car starts from rest on a horizontal circular track of 115-m radius and increases its speed at a uniform rate to reach 90

Wewaii [24]

Answer:

a= 3.49 m/s^2

Explanation:

magnitude of total acceleration = sqrt{radial acceleration^2+tangential acceleration^2}.

we know that tangential acceleration a_t= change in velocity /time taken

now 90 km/h = 25 m/s

a_t = 25/17 = 1.47 m/s^2.

radial acceleration a_r = v^2/r

v= a_t×t = 1.47×13 = 19.11 m/s

a_r = 19.11^2/115= 3.175

now,

$a= \sqrt{a_t^2+a_r^2}$

$a= \sqrt{1.47^2+3.175^2}$

a= 3.49 m/s^2

3 0

3 years ago

To overcome the problems that blur images and don't provide the best resolution from Earth, astronomers have started using flexi

schepotkina [342]

Answer:

adaptive optics

Explanation:

simple

3 0

2 years ago

C) An identical spring is pulled with a force or 75 N The elastie limit of the spring is 72N

tiny-mole [99]

Answer:

Spring cannot return to its original, since a part of its deformation is plastic, not elastic.

Explanation:

Physically speaking, stress is equal to the axial force divided by effective transversal area of spring. In addition, springs have usually a linear relationship between stress and strain in elastic region, since they are made of ductile materials. Axial force is directly proportional to axial stress, which is also directly proportional to axial strain.

Then, if force is greater than force associated with elastic limit of the spring, then spring cannot return to its original, since a part of its deformation is plastic, not elastic.

8 0

3 years ago