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3 years ago

What other theory does the author compare to the Big Bang to?

Physics

1 answer:

sveta [45]3 years ago

7 0

Answer:

The two Russian authors based their exposition on what they called the Friedmann theory of a singular beginning of the universe, referring throughout to the “theory of the hot universe” as an alternative to the hot Big Bang theory.

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A 1500 kg car is moving on a flat, horizontal flat road. If the radius of the curve is 35 m and

Troyanec [42]

The net force on the car is the friction that keeps it on the road, which points toward the center of the circle of the curve. Then by Newton's second law, we have

• net vertical force:

∑ F = N - W = 0

• net horizontal force:

∑ F = Fs = m a

where

N = magnitude of normal force

W = car's weight

Fs = mag. of static friction

m = car's mass

a = v ²/R = mag. of the centripetal acceleration

v = car's speed

R = radius of curve

Now,

• compute the car's weight:

W = m g = (1500 kg) (9.8 m/s²) = 14,700 N

• solve for the mag. of the normal force:

N = 14,700 N

• solve for the mag. of the friction force, using the given friction coefficient:

Fs = 0.5 N = 7350 N

• solve for the (maximum) acceleration:

7350 N = (1500 kg) a → a = 4.9 m/s²

• solve for the (maximum) speed:

4.9 m/s² = v ²/ (35 m) → v ≈ 13 m/s

4 0

3 years ago

What are three common clues that a chemical change has occurred

ddd [48]

The substance has changed, It dissolved, and it evaproted.

6 0

3 years ago

As the shuttle bus comes to a sudden stop to avoid hitting a dog, it accelerates uniformly at -4.1 m/s2 as it slows from 9.0 m/s

Dennis_Churaev [7]

Answer:

The time interval of acceleration for the bus is 2.20 seconds

Explanation:

Acceleration is the rate of change of velocity

→ $a=\frac{v-u}{t}$

where a is the acceleration, v is the final velocity, u is the initial velocity

and t is the time

The given is:

The uniform acceleration = -4.1 m/s²

The bus slows from 9 m/s to 0 m/s

We need to find the time interval of acceleration for the bus

Lets use the rule above

→ a = -4.1 m/s² , v = 0 m/s , u = 9 m/s

→ $-4.1=\frac{0-9}{t}$

Multiply both sides by t

→ -4.1 t = -9

Divide both sides by -4.1

∴ t = 2.20 seconds

The time interval of acceleration for the bus is 2.20 seconds

3 0

4 years ago

How is electron affinity different from electronegativity

NeTakaya

Explanation:

Electronegativity is the ability of an atom to attract electrons, when it forms a chemical bond in a molecule. However, it is not strictly an atomic property, since it refers to an atom within a molecule. The equivalent property of electronegativity for an isolated atom is electronic affinity.

3 0

3 years ago

An electron moves in a region where the magnetic field is uniform and has a magnitude of 80 μT. The electron follows a helical p

sladkih [1.3K]

Answer:

3.4 x 10⁴ m/s

Explanation:

Consider the circular motion of the electron

B = magnetic field = 80 x 10⁻⁶ T

m = mass of electron = 9.1 x 10⁻³¹ kg

v = radial speed

r = radius of circular path = 2 mm = 0.002 m

q = magnitude of charge on electron = 1.6 x 10⁻¹⁹ C

For the circular motion of electron

qBr = mv

(1.6 x 10⁻¹⁹) (80 x 10⁻⁶) (0.002) = (9.1 x 10⁻³¹) v

v = 2.8 x 10⁴ m/s

Consider the linear motion of the electron :

v' = linear speed

x = horizontal distance traveled = 9 mm = 0.009 m

t = time taken = $\frac{2\pi m}{qB}$ = $\frac{2\pi (9.1\times 10^{-31})}{(1.6\times 10^{^{-19}})(80\times 10^{-6})}$ = 4.5 x 10⁻⁷ sec

using the equation

x = v' t

0.009 = v' (4.5 x 10⁻⁷)

v' = 20000 m/s

v' = 2 x 10⁴ m/s

Speed is given as

V = sqrt(v² + v'²)

V = sqrt((2.8 x 10⁴)² + (2 x 10⁴)²)

v = 3.4 x 10⁴ m/s

6 0

3 years ago