All categories

3 years ago

The total number of stars in the observable universe is roughly equivalent to:

Physics

1 answer:

musickatia [10]3 years ago

3 0

Answer:

The number of grains of sand on all the beaches on Earth

Explanation:

if we assume grain of sand has an average size , then the number of grains of sand on all the beaches on Earth is roughly $7.5 \times 10^{18}$

The total number of stars in the observable universe is roughly equivalent to 1 billion trillion. which is roughly equal to the number of grains of sand on all the beaches on Earth.

You might be interested in

Suppose you put an ice cube into a cup of hot tea. In what direction does energy in the form of heat flow? What happens to the i

Semenov [28]

Answer:

The energy flows between the ice and the tea equally. The table below shows the temperatures of several different objects made of the same material.

6 0

3 years ago

A motorcycle is following a car that is traveling at constant speed on a straight highway. Initially, the car and the motorcycle

xz_007 [3.2K]

Answer:

a) $\Delta{t} = 5.39s$

b) the motorcycle travels 155 m

Explanation:

Let $t_2-t_1 = \Delta{t}$ , then consider the equation of motion for the motorcycle (accelerated) and for the car (non accelerated):

$v_{m2}=v_0+a\Delta{t}\\x+d=(\frac{v_0+v_{m2}}{2} )\Delta{t}\\v_c = v_0 = \frac{x}{\Delta{t}}$

where:

$v_{m2}$ is the speed of the motorcycle at time 2

$v_{c}$ is the velocity of the car (constant)

$v_{0}$ is the velocity of the car and the motorcycle at time 1

d is the distance between the car and the motorcycle at time 1

x is the distance traveled by the car between time 1 and time 2

Solving the system of equations:

$\left[\begin{array}{cc}car&motorcycle\\x=v_0\Delta{t}&x+d=(\frac{v_0+v_{m2}}{2}}) \Delta{t}\end{array}\right]$

$v_0\Delta{t}=\frac{v_0+v_{m2}}{2}\Delta{t}-d \\\frac{v_0+v_{m2}}{2}\Delta{t}-v_0\Delta{t}=d\\(v_0+v_{m2})\Delta{t}-2v_0\Delta{t}=2d\\(v_0+v_0+a\Delta{t})\Delta{t}-2v_0\Delta{t}=2d\\(2v_0+a\Delta{t})\Delta{t}-2v_0\Delta{t}=2d\\a\Delta{t}^2=2d\\\Delta{t}=\sqrt{\frac{2d}{a}}=\sqrt{\frac{2*58}{4}}=\sqrt{29}=5.385s$

For the second part, we need to calculate x+d, so you can use the equation of the car to calculate x:

$x = v_0\Delta{t}= 18\sqrt{29}=96.933m\\then:\\x+d = 154.933$

3 0

3 years ago

Question 8

Viefleur [7K]

Answer:

96 Joules

Explanation:

The formula for work is Fnet times displacement (F x d = w) which, in this case, 48N is the Fnet and 2m as the displacement. Then all we need to do is multiply these two and we get 96 Joules.

3 0

3 years ago

If the horizontal component of a vector is 6 m/s and the vertical component is also 6 m/s, what is the resultant value of the ve

BlackZzzverrR [31]

Resultant force= (2*6^2)^(1/2)
=8.5m/s
answer is B.

6 0

3 years ago

Which is a vector quantity, speed or velocity? defend your answer.

krek1111 [17]

<span>Speed is the distance traveled divided by the time it took to travel this distance. Velocity is the change in position divided by the time of travel. Velocity only depends on the starting and ending point but the speed depends on the path. Speed is a scalar quantity (the distance per time ratio) and velocity is a vector quantuty, because it is defined also with its direction.</span>

4 0

3 years ago