What force pulls the truck/ramp down towards the track? Group of answer choices

An object is made of glass and has the shape of a cube 0.13 m on a side, according to an observer at rest relative to it. Howeve

Vlad1618 [11]

Answer:

$v=0.9833\ c$

Explanation:

The density changes means that the length in the direction of the motion is changed.

Therefore,

$\text{Density} = \frac{m}{lwh}$

Given :

Side, b = h = 0.13 m

Mass, m = 3.3 kg

Density = 8100 $kg/m^3$

So,

$8100=\frac{3.3}{l \times 0.13 \times 0.13}$

$l=\frac{3.3}{8100 \times 0.13 \times 0.13}$

l = 0.024 m

Then for relativistic length contraction,

$l= l' \sqrt{1-\frac{v^2}{c^2}}$

$0.024= 0.13 \sqrt{1-\frac{v^2}{c^2}}$

$0.184= \sqrt{1-\frac{v^2}{c^2}}$

$0.033= 1-\frac{v^2}{c^2}}$

$\frac{v^2}{c^2}= 0.967$

$\frac{v}{c}=0.9833$

$v=0.9833\ c$

Therefore, the speed of the observer relative to the cube is 0.9833 c (in the units of c).

3 0

3 years ago

Pls answer I will make brainlist

Semenov [28]

Reflection: a change in direction of a wave at a boundary between two different media.
sentence: i saw my reflection in the mirror.

refraction: the bending of light as it passes from one transparent substance into another.
sentence: when light goes through glass, it’s a refraction.

diffraction: the bending of waves around the corners of an obstacle.
sentence: spaced tracks on a CD act as a diffraction.

absorption: the process or action by which one thing absorbs or is absorbed by another.
sentence: heat waves hitting the beach usually give most of their energy to the sand.

interference: when two waves lay on each other and their energies are either added together or cancelled out.
sentence: interference waves can be observed with all types of waves.

standing wave: two waves moving in opposite directions. they both have the same amplitude or frequency.
sentence: plucking the string of a guitar is an example of standing waves.

resonance: increased amplitude that occurs when the frequency of a force is equal or close to a natural frequency.
sentence:a buzz in your car that only occurs at a certain speed is an example or resonance.

3 0

3 years ago

Calculate the mass of a liquid with a density of 2.5 g/ml and a volume of 15ml

Nana76 [90]

Using the density equation and clearing mass:

$\rho = \frac{m}{V}\ \to\ m = \rho\cdot V = 2.5\frac{g}{mL}\cdot 15\ mL = \bf 37.5\ g$

3 0

3 years ago

Pressure is about 1000 hPa at sea level and about 500 hPa at an altitude of 5.5 km. Why doesn’t this vertical pressure gradient

saul85 [17]

Answer:

A. The upward pressure gradient force is balanced by gravity.

Explanation:

A. is correct because the pressure difference is actually generated by gravity. As in the following formula for the pressure at different points:

$p = p_0 + \rho g h$

where $p, p_0$ are the pressure at 2 points, ρ is the density of the fluid, g is the gravitational constant, and h is the height difference.

B is incorrect because friction in air is too small to make an effect.

C is incorrect because the Coriolis force is horizontal, not vertical.

D is incorrect because a difference of 500 hPa = 50000 Pa, this is half of the atmospheric pressure.

E is incorrect because temperature cannot generate force.

6 0

3 years ago

Inside a car that was at 273 K, a bottle with a pressure at 100,000 pascals warms up to

Deffense [45]

Answer:

P2 = 128,205 pascal.

Explanation:

Given the following data;

Original Pressure, P1 = 100,000 pascals

Original Temperature, T1 = 273K

New Temperature, T2 = 350K

To find new pressure P2, we would use Gay Lussac' law.

Gay Lussac's law states that when the volume of an ideal gas is kept constant, the pressure of the gas is directly proportional to the absolute temperature of the gas.

Mathematically, Gay Lussac's law is given by;

$PT = K$