Where are some of Earth's youngest rocks found?

Five identical quintuplets leave earth when they reach the age of 21, in the year 2121. Each quintuplet goes on a spaceship jour

Elena-2011 [213]

Answer:

Explanation:

This is a problem based on time dilation , a theory given by Albert Einstein .

The formula of time dilation is as follows .

t₁ = $\frac{t}{\sqrt{1-\frac{v^2}{c^2} } }$

t is time measured on the earth and t₁ is time measured by man on ship .

A ) Given t = 20 years , t₁ = ? v = .4c

$\frac{20}{\sqrt{1-\frac{.16c^2}{c^2} } }$

=1.09 x 20

t₁= 21.82 years

B ) Given t = 5 years , t₁ = ? v = .2c

$\frac{5}{\sqrt{1-\frac{.04c^2}{c^2} } }$

=1.02 x 5

t₁= 5.1 years

C ) Given t = 10 years , t₁ = ? v = .8c

$\frac{10}{\sqrt{1-\frac{.64c^2}{c^2} } }$

=1.67 x 10

t₁= 16.7 years

D ) Given t = 10 years , t₁ = ? v = .4c

$\frac{10}{\sqrt{1-\frac{.16c^2}{c^2} } }$

=1.09 x 10

t₁= 10.9 years

E ) Given t = 20 years , t₁ = ? v = .8c

$\frac{20}{\sqrt{1-\frac{.64c^2}{c^2} } }$

=1.67 x 20

t₁= 33.4 years

7 0

3 years ago

The brakes exert a 1,951 N force on a car weighing 18,985 N and moving at 12 m/s. The car finally stops. How long (in seconds) d

nata0808 [166]

Answer:20,000

Explanation:

7 0

4 years ago

A physical pendulum consists of a meter stick that is pivoted at a small hole drilled through the stick a distance d from the 50

PSYCHO15rus [73]

Answer:

(a). The value of d is 0.056 cm and 1.496 cm.

(b). The time period is 1.35 sec.

Explanation:

Given that,

Length = 50.00 cm

Time period = 2.50 s

Time period of pendulum is defined as the time for one complete cycle.

The period depends on the length of the pendulum.

Using formula of time period

$T=2\pi\sqrt{\dfrac{I}{mgh}}$

Where, I = moment of inertia

We need to calculate the value of d

Using parallel theorem of moment of inertia

$I=I_{cm}+md^2$

For a meter stick mass m , the rotational inertia about it's center of mass

$I_{cm}-\dfrac{mL^2}{12}$

Where, L = 1 m

Put the value into the formula of time period

$T=2\pi\sqrt{\dfrac{\dfrac{mL^2}{12}+md^2}{mgd}}$

$T=2\pi\sqrt{\dfrac{L^2}{12gd}+\dfrac{d}{g}}$

$T^2=4\pi^2(\dfrac{L^2}{12gd}+\dfrac{d}{g})$

Multiplying both sides by d

tex]T^2d=4\pi^2(\dfrac{L^2}{12g}+\dfrac{d^2}{g})[/tex]

$(\dfrac{4\pi^2}{g})d^2-T^2d+\dfrac{\pi^2L^2}{3g}=0$

Put the value of T, L and g into the formula

$4.028d^2-6.25d+0.336=0$

$d = 0.056\ m, 1.496\ m$

The value of d is 0.056 cm and 1.496 cm.

(b). Given that,

L = 50-5 = 45 cm

We need to calculate the time period

Using formula of period

$T=2\pi\sqrt{\dfrac{l}{g}}$

Put the value into the formula

$T=2\pi\sqrt{\dfrac{45\times10^{-2}}{9.8}}$

$T=1.35\ sec$

Hence, (a). The value of d is 0.056 cm and 1.496 cm.

(b). The time period is 1.35 sec.

7 0

3 years ago

Hat do peaked roofs, convertible tops, and airplane wings have in common when air moves faster across their top surfaces? What d

Nutka1998 [239]

Answer:

a.

Explanation:

The air moves faster across the top of the surface and exerts less pressure on the air below and thus due to difference in air pressure the top roof is lifted.

hence the correct option is pressure underneath them is reduced.

6 0

3 years ago

Read 2 more answers

A Jaguar XK8 convertible has an eight-cylinder engine. At the beginning of its compression stroke, one of the cylinders contains

Colt1911 [192]

If only I was smart then I could help you :/ no but like for real im madddd dumb sorry :(

4 0

4 years ago